NUREG/CR-6369, Vol. 1

SEA 97-3105-A: 14

Drywell Debris Transport

Study

Final Report

Science and Engineering Associates, Inc.

U.S. Nuclear Regulatory Commission

Office of Nuclear Regulatory Research

Washington, DC 20555-0001
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NUREG/CR-6369, Vol. 1

SEA 97-3105-A: 14

Drywell Debris Transport Study

Final Report

Manuscript Completed: February 1998

Date Published: September 1999

Prepared by

D. V. Rao, C. Shaffer, E. Haskin

Science and Engineering Associates, Inc.

6100 Uptown Blvd. NE

Albuquerque, NM 87110

Prepared for

Division of Engineering Technology

Office of Nuclear Regulatory Research

U.S. Nuclear Regulatory Commission

Washington, DC 20555-0001

NRC Job Code W6325
NUREG/CR-6369, Volume 1, has been

reproduced from the best available copy.

Some of the pages in this publication were

intentionally omittted.

For sale by the U.S. Government Printing Office

Superintendent of Documents, Mail Stop: SSOP, Washington, DC 20402-9328

ISBN 0-16-050193-8
Abstract

This report describes results of the drywell debris transport study. The objective of the study is to develop a methodology for

estimating fraction of LOCA generated fibrous insulation debris that would be transported from the location of their

generation in the drywell to the suppression pool. The study decomposed the problem into several components that were

amenable to resolution by the knowledge base that can be developed from separate effects experiments, analytical modeling,

and engineering calculations. Experiments and analytical studies were undertaken to compile the necessary knowledge base

on debris transport during blowdown, washdown of debris by ECCS water flow, and debris sedimentation on the drywell

floor. Logic charts were used to link both experimental and analytical results. The results of the study were used to delineate

plant features and transport phenomena that dominate debris transport in the BWR drywell. A separate logic chart was

developed for each postulated accident scenario and generic plant type analyzed. The logic charts can be modified to take

into account effects of the plant-specific features. The overall method is comprehensible to engineers who are not experts in

the subject of debris transport. Also, it is sufficiently flexible that new evidence and assumptions, related to debris size and

distribution, can be easily accommodated.

iii NUREG/CR-6369
Table of Contents

Page

Abstract .................................................................... iii

Executive Summary ........................................................ ix

Acknowledgments . .................................................................... xiii

Acronyms....................................................................................... Xiv

1 Introduction .................................................................. 1-1

1.1 Background and Objectives . ........................................................ 1-1

1.2 Program Overview and Report Outline ...................................................... 1-2

1.3 References . .................................................................... 1-4

2 Methodology Overview ............... ......................................... 2-1

2.1 Debris Transport Pathways.. 2-1

2.1.1 Blowdown Transport (Short-term) .2-4

2.1.2 Washdown Transport (Long-term) .2-9

2.2 Debris Size Considerations .. 2-17

2.3 Identification of Controlling Phenomena and Plant Features .. 2-17

2.4 Debris Transport Factor Quantification .. 2-17

2.4.1 Plant Design.2-29

2.4.2 Selection of Break Type and Location .2-29

2.4.3 ECCS Throttling .2-29

2.4.4 Drywell Spray Operation .2-29

2.5 References .. 2-29

3 Controlling Phenomena and Plant Features .3-1

3.1 Controlling Plant Features .. 3-1

3.1.1 Effect of Floor Gratings .3-1

3.1.2 Vent and Drywell Floor Design .3-1

3.1.3 Duration of Unthrottled ECCS Operation .3-5

3.2 Dominant Transport Processes .. 3-5

3.2.1 Small Debris.3-5

3.2.2 Large Debris .3-5

3.2.3 Large Canvassed .3-8

3.3 References .3-8

4 Quantification of Logic Charts .. 4-1

4.1 Main Steam Line Break Logic Chart .4-1

4.1.1 Debris Generation .. 4-1

4.1.1.1 Key Findings .4-4

4.1.1.2 Upper Bound Estimates .4-6

4.1.1.3 Central Estimates .4-6

v NUREG/CR-6369
Contents (continued)

Page

4.1.2 Distribution at the End of Blowdown ..... ...... .. ............. 4-6

4.1.2.1 Key Findings .......................... 4-7

4.1.2.2 Upper Bound Estimates .......................... 4-11

4.1.2.3 Central Estimates .......................... 4-13

4.1.3 Erosion and Washdown .......................... 4-18

4.1.3.1 Key Findings .......................... 4-18

4.1.3.2 UpperBound .......................... 4-18

4.1.3.3 Central Estimate .......................... 4-18

4.1.4 Drywell Floor Pool Transport .......................... 4-19

4.1.4.1 Key Findings .......................... 4-19

4.1.4.2 Upper Bound .......................... 4-19

4.1.4.3 Central Estimate .......................... 4-23

4.1.5 Results of Quantification ........... .. ............. 4-23

4.1.5.1 Upper Bound .......................... 4-23

4.1.5.2 Central Estimate .......................... 4-23

4.2 Recirculation Line Break ................. 4-23

4.2.1 Debris Classification ........... ............... 4-27

4.2.1.1 Key Findings .......................... 4-27

4.2.1.2 UpperBound .......................... 4-30

4.2.1.3 Central Estimates .......................... 4-30

4.2.2 Distribution at the End of Blowdown ............ .............. 4-30

4.2.2.1 Key Findings .......................... 4-30

4.2.2.2 Upper Bound Estimates .......................... 4-31

4.2.2.3 Central Estimates .......................... 4-31

4.2.3 Erosion and Washdown ........... ............... 4-31

4.2.3.1 Key Findings .......................... 4-33

4.2.3.2 Upper Bound .......................... 4-33

4.2.3.3 Central Estimate .......................... 4-33

4.2.4 Drywell Floor Pool .. ........................ 4-33

4.2.4.1 Upper Bound .......................... 4-33

4.2.4.2 Central Estimate .......................... 4-36

4.2.5 Results of Quantification .......................... 4-36

4.2.5.1 Upper Bound .......................... 4-36

4.2.5.2 Central Estimate .......................... 4-36

4.3 References ........ 4-36

5 Application of the Study Results ...................... ....................... 5-1

5.1 Integration of Debris Generation Data ................. ............................ 5-1

5.2 Deviations from the Assumed Generic Plant Geometry .......................................... 5-2

5.3 References .............................................. 5-14

Appendix A Compilation of Debris Transport Study Logic Charts .A-1

NUREG/CR-6369 vi
FIGURES

Page

E- 1 Postulated debris transport pathways and experiments/analyses conducted to

compile the necessary knowledge base .......................................................... x

1-1 Programmatic overview of the drywell debris transport study ........................................ 1-3

2-1 Postulated debris transport pathways in a Mark I BWR ............. ................................. 2-2

2-2 Transport pathways in a BWR ............................................................... 2-3

2-3 Data gathered to evaluate drywell debris transport during blowdown (short-term) phase ..... .............. 2-13

2-4 Data gathered to evaluate drywell debris transport during washdown (long-term) phase .

2-5

2-6

2-7

2-8

2-9

2-10

3-1

3-2

3-3

3-4

3-5

4-1

4-2

4-3

4-4

4-5

4-6

4-7

4-8

4-9

4-10

4-11

4-12

4-13

4-14

4-15

4-16

4-17

4-18

4-19

5-1

5-2

5-3

5-4

5-5

5-6

A photograph of small size insulation debris produced in air-jet tests .......

A photograph of large size insulation debris produced in air-jet tests ........

A photograph of large canvassed debris produced in air-jet tests ...........

A photograph of shredded canvas debris produced in air-jet tests ..........

Generic logic chart used for quantification of debris transport .............

Accident scenarios analyzed in the study .............................

Typical small debris deposition on wet gratings observed in the experiments .

Capture of large debris on dry/wet gratings ...........................

Capture of small debris around simulation Mark II vent ..................

Erosion of large debris trapped on floor grating by water flow .............

Erosion as a function of time for large pieces trapped on floor grating ......

Logic chart for upper bound estimate of transport factor for a MSLB scenario.

Logic chart for central estimate of transport factor for a MSLB scenario .....

............. 2-14

............. 2-21

............. 2-21

............. 2-22

............. 2-22

............. 2-25

............. 2-28

.............. 3-2

.............. 3-3

.............. 3-4

.............. 3-6

.............. 3-7

............................ 4-2

............................ 4-3

Blowdown data corresponding to a postulated main steam line break in a BWR/4 plant. .................... 4-5

MELCOR predictions for drywell thermal hydraulics response following a MSLB ........................ 4-8

CFD code predictions for quasi-steady flow patterns that exist in the drywell following a MSLB ... .......... 4-9

Liquid film build-up on drywell structures due to steam condensation .................................. 4-12

Secondary logic tree used to evaluate upper bound debris distribution after blowdown .... ................ 4-14

Efficiency for capture of small debris by floor grating .............................................. 4-15

Secondary logic tree used to obtain the central estimate for debris distribution after blowdown ... ........... 4-16

Structure capture fraction ................................................................... 4-17

Flow velocities at overflow level for containment spray pool in Mark I ................................. 4-20

Specific kinetic energies for containment spray pool in Mark I ....................................... 4-21

Logic chart for upper bound estimate of transport factor for a RLB scenario ............................. 4-25

Logic chart for central estimate of transport factor for a RLB scenario ................................. 4-26

Blowdown data corresponding to a postulated recirculation line break in a BWR/4 ....................... 4-28

Expansion of high speed water jet in a region with structural impediments .............................. 4-29

Logic used to estimate distribution at the end of blowdown .......................................... 4-32

Flow velocities at overflow level for full recirculation flow from broken pipe in Mark I .... ............... 4-34

Specific kinetic energies for full recirculation flow from broken pipe in Mark I .......................... 4-35

Upper bound logic chart with BWROG size distribution data ......................................... 5-6

Central estimate logic chart with BWROG site distribution data ....................................... 5-7

Effect of upper floor grating on upper bound estimate of debris distribution after blowdown ... .............. 5-8

Effect of upper grating on central estimate debris distribution after blowdown ............................ 5-9

Upper bound logic tree for debris transport in a Mark I drywell with one floor grating ..................... 5-10

Central estimate logic tree for debris transport in a Mark I drywell with one floor grating ... ............... 5-11

vii NUREG/CR-6369
TABLES

2-1 Overview of separate effects test program . ....................................................... 2-7

2-2 Overview of integrated experimental program .............. ...................................... 2-11

2-3 Overview of washdown experimental program .............. ...................................... 2-15

2-4 Overview of CFD simulation of transport in drywell pool ........................................... 2-19

2-5 Debris classification ..................................................................... 2-23

4-1 Upper bound estimate of debris transport fractions for a MSLB scenario ............................... 4-22

4-2 Central estimate of debris transport fractions for a MSLB scenario .................................... 4-24

4-3 Upper bound estimate of debris transport fractions for a RLB scenario ................................. 4-37

4-4 Central estimate of debris transport fractions for a RLB scenario ...................................... 4-38

5-1 Debris size distribution data used in example 1 ............... ...................................... 5-2

5-2 Upper bound estimates for debris transport based on BWROG size distribution data ....................... 5-3

5-3 Central estimate for debris transport based on BWROG size distribution data ............................. 5-4

5-4 Center and upper bound estimates for debris transport factors based on BWROG size

distribution data . ..................................................................... 5-5

5-5 Upper bound transport factors for debris transport in a Mark I drywell with one floor grating ..... .......... 5-12

5-6 Central estimate transport factors for debris transport in a Mark I drywell with one floor grating ..... ........ 5-13

NUREG/CR-6369 . . .
Executive Summary

A loss of coolant accident (LOCA) in a boiling water

reactor (BWR) would destroy fibrous insulation blankets

and generate fibrous debris in a region close to the break

referred to as the zone of influence (ZOI). This debris

would be carried away from the zone of influence by high

velocity steam flow, in the case of a main steam line

break (MSLB), and by steam-water mixtures, in the case

of a recirculation line break (RLB). The debris entrained

by the vapor flow would be transported across the drywell

volume through floor gratings to the drywell floor where

it enters the vent pipes (or downcomers). However, the

drywell presents numerous impediments to such transport

in the form of I-beams, floor gratings, pipes, instrument

panels, etc., where the debris may become attached or

trapped. The remaining debris would be transported to

the suppression pool during blowdown phase, within

minutes after a LOCA.

Following blowdown, water would be introduced into the

drywell by break overflow or drywell sprays. Water from

the drywell sprays covers 100% of the drywell structures

located underneath the sprays, whereas water from break

flow spreads over a limited cross-section of the drywell

located directly beneath the break. In both cases, as the

water cascades down from the location of its introduction

it would washdown (i.e., re-entrain or erode) some of the

debris captured on (or trapped by) the drywell structures

during blowdown. The washed down debris would be

brought to the drywell floor where water accumulates to

form a pool until the water level rises above the vent or

downcomer entrance. The pool height and the pool flow

dynamics, including turbulence levels are highly plantspecific, controlled by such features as the water flow

rate, height from which water falls into the pool, vent pipe

offset and type of structures located close to the floor.

Depending on the pool dynamics, the debris brought to

the floor may remain in suspension or may sediment. The

fraction that remains in suspension will ultimately be

transported to the vents (or downcomers) as the water

flows into them.

As shown in Figure E- 1, debris transport is a complex

process occurring over two distinct phases: blowdown

and washdown. The objective of the drywell debris

transport study (DDTS) is to investigate debris transport

using a bounding analysis approach to estimate the

fraction of the debris transported by blowdown and

washdown processes and to identify important

phenomena and plant features that control or dominate

debris transport. The results of the DDTS would form the

basis by which NRC can judge the accuracy of the debris

transport factors used in the utility strainer blockage

analyses.

SEA undertook the DDTS in September 1996. The first

step of the DDTS was to perform an end-to-end scoping

calculation to understand the thermal and hydraulic

conditions that would govern debris transport. Based on

these calculations, the overall transport problem was

decomposed into several components that were amenable

to resolution by the knowledge base that can be

developed from separate effects experiments, analytical

modeling and engineering calculations. The calculations

also identified vital data necessary to quantify transport.

Experiments and analytical studies were undertaken to

compile the necessary knowledge base on debris transport

during blowdown, washdown of debris by ECCS water

flow, and debris sedimentation on the drywell floor. In

particular, three experiments were designed and

conducted as part of this study. The first two experiments

studied inertial capture of fibrous insulation fragments

during air-borne transport on typical drywell structures.

The third experiment studied washdown of debris

previously deposited on various drywell structures by

break overflow and containment sprays. In addition,

detailed CFD simulations were used to determine flow

patterns that would likely exist on the drywell floor

during ECCS recirculation and the likelihood of debris

sedimentation under these conditions. The study relied

primarily on this knowledge base to quantify importance

of each transport pathway. Although analytical tools

(e.g., MELCOR and RELAP) were used in the study,

their usage was limited to gathering information

regarding selected aspects of the overall problem.

The results of the study were used to delineate plant

features and transport phenomena that dominate debris

transport in the BWR drywell. Three such plant features

were identified: (I) number and arrangement of gratings

with respect to the break, (2) duration of unthrottled

ECCS flow, and (3) vent and drywell floor design.

Experimental data clearly illustrated that during

blowdown, the drywell

lX NUREG/CR-6369
Method of Study:

CFD Simulations of Drywell Floor Pool

ARLUPPL Flume Transport of Debris

Figure E-1. Postulated debris transport pathways and experiments/analyses

conducted to compile the necessary knowledge base.

NUREG/CR-6369 x
floor gratings provide the largest potential for

capture of both small and large debris, with capture

efficiencies between 15% and 30% for small debris

and 100% for large debris. The small pieces

captured on gratings can be easily re-entrained by

ECCS water flow during washdown. The only

mechanism available for washdown of large pieces

is erosion, which was found to be a constant rate

process. Therefore, time assumed for unthrottled

operation of ECCS plays a key role in determining

the fraction of large pieces that would be washed

down. Although vents may provide an effective

location for capture during blowdown, the captured

debris may become re-entrained by the drywell pool

flow dynamics. Typically, higher flow velocities and

turbulence levels characterize pools formed as a

result of break over flow. Sedimentation of small or

large debris in such pools is unlikely. On the other

hand, sedimentation is likely in the pools formed by

containment sprays.

A simplified logic chart method was chosen to link

both experimental and analytical results. A separate

logic chart was developed for each postulated

accident scenario and generic plant type analyzed. A

total of twenty accident scenarios covering three

plant types (Mark I, II and III), two break types

(MSLB and RLB) and a variety of assumptions

regarding ECCS response were analyzed. For each

scenario two types of transport factors were

obtained. The upper bound estimates were obtained

by compounding bounding estimates for the effect ot

each transport pathway. It is extremely unlikely that

transport following a LOCA would exceed upper

bound estimates. The central estimates are judged to

be a more realistic representation of debris transport.

The study estimates that a large fraction of small debris

and large debris produced below the lowest grating

would be transported to the vents. However, only a

small fraction of the large debris generated above the

lowest grating would be transported. No transport

pathways were identified for canvas covered large

pieces. The total fraction of debris transported depends

strongly on the assumed size distribution of the debris

and the location of the break. Table E-1 presents upper

bound and central estimates for the transport factor

corresponding to each accident scenario analyzed for a

postulated LOCA in the mid-region of the drywell

assuming BWROG recommended debris size

distribution.

Transport factor estimates presented in Table E-1 were

obtained based on an assumed set of generic plant

features (e.g. floor gratings). Plant specific usage of

these factor should be subject to a review to assure that

all plant features were properly modeled in this study.

If necessary, the logic charts provided in this study can

be easily modified to account for plant-specific

features, such as number and arrangement of floor

gratings. Also, they are sufficiently flexible to

accommodate new evidence and assumptions related

to debris size and distribution.

Table E-1. Upper bound and central estimates for transport factor associated with a postulated

LOCA in the mid-region of the drywell using BWROG size distribution.

Central Estimate Upper Bound Estimate

Containment/Break Small Large Debris Small Large Debris

Debris Above Below Debris Above Below

Grating Grating Grating Grating

Mark I

Main Steam Line Break 0.52 0.01 0.90 1.0 0.05 1.0

Recirculation Line Break 0.86 0.02 0.94 1.0 0.30 1.0

Mark II

Main Steam Line Break 0.74 0.01 0.90 1.0 0.05 1.0

Recirculation Line Break 0.89 0.02 0.95 1.0 0.30 1.0

Mark III

Main Steam Line Break 0.55 0 0.90 0.93 0.03 1.0

Recirculation Line Break 0.72 0.01 0.90 1.0 0.30 1.0

xi NUREG/CR-6369
Acknowledgements

The authors would like to acknowledge contributions of numerous individuals and several organizations. First, the study

could not have been completed without the technical and management support from the US Nuclear Regulatory Commission.

Mr. Michael Marshall (NRC/RES) is the NRC task manager for the drywell debris transport study and provided critical

technical direction at different times, participated in the experiments, and performed an in depth review of the results. Mr.

Robert Elliott (NRC/NRR) and Mr. Aleck Serkiz provided valuable regulatory viewpoint and historical perspective,

respectively.

Several SEA staff members provided key technical assistance at critical junctures. Ms. Jane Brideau was responsible for

program management and technical report preparation. Mr. Frank Sciacca provided valuable help during Phase 1 study,

including design of the experimental program. Mr. Brian Carpenter and Mr. David Cremer played a key role in designing

and conducting CEESI experiments, without whose hard work the tests could not have been conducted on time or within

budget. Similarly, Ms. Kami Burr and Mr. Jerry Stockton were responsible for the design of washdown experiments and Mr.

Kirk Weingardt was solely responsible for conducting the experiments and drying the insulation. Ms. Rose Flores and Janice

Johnston is responsible for typing and producing this report.

Mr. George Hecker who participated in this study since its inception led the experimental efforts at ARL; with assistance

from Dr. Mahadevan Padmanabhan and Mr. Phil Stacey. Authors would like to express sincere gratitude to them.

The authors also received valuable input from the Phenomena Identification and Ranking Table (PIRT) Panel members: Drs.

Ken Williams, Mark Leonard, Brent Boyack, Lothar Wolf, and Gary Wilson. They played an important role during

experimental program design and methodology development.

. . . NUREG/CR-6369
ACRONYMS

ARL Alden Research Laboratory Inc.

BWR Boiling water reactor

BWROG Boiling Water Reactor's Owners Group

CEESI Colorado Engineering Experiment Station

CFD Computational fluid dynamics

DDTS Drywell debris transport study

ECCS Emergency core cooling system

GPM Gallons per minute

LOCA Loss of coolant accident

MSL Mean steam line

MSLB Main steam line break

NRC U.S. Nuclear Regulatory Commission

PIRT Phenomena Identification and Ranking Table

PP&L Pennsylvania Power and Light Company

PVC Polyvinyl chloride

RLB Recirculation line break

SEA Science and Engineering Associates, Inc.

ZOI Zone of influence

NUREG/CR-6369 xiv
1. Introduction

1.1 Background and Objectives

In 1993, the U. S. Nuclear Regulatory Commission

(NRC) initiated an evaluation of the potential of loss

of coolant accident (LOCA) generated debris to

block boiling water reactor (BWR) suction strainers

and prevent the emergency core cooling systems

(ECCS) from performing their long-term cooling

function [Ref. 1.1]. In 1995, Science and Engineering

Associates, Inc. (SEA) completed the NUREG/CR6224 study, which analyzed that potential for a

reference plant. The study concluded that LOCA

generated debris have a high likelihood of

accumulating on the ECCS suction strainers

following a LOCA event, and that this accumulation

could cause excessive head loss, disabling the ECCS

pumps within a short duration [Ref. 1.2].

NUREG/CR-6224 postulated that insulation debris

generated in the drywell would be transported to

the wetwell over two phases: (1) blowdown phase,

during which steam/gas flow would entrain and

transport debris to the suppression pool; and

(2) washdown phase, where water flowing out of the

break and/or containment sprays will transport a

fraction of the remaining debris. The NUREG/CR6224 analyses reasoned that the congested layout

closer to the gratings would offer a large surface

area for debris retention. This formed the basis for

dividing the reference plant containment into three

regions (High-, Mid-, and Low- Regions) with

reference to the two gratings, and for assuming that

the fraction of debris transported to the suppression

pool would vary depending on the region in which

it was generated'. However, due to the lack of

directly applicable experimental or analytical data,

this fraction, termed the transport factor, was

estimated based on engineering judgement derived

from the analysis of the Barseback-2 event data [Ref.

1.2 and 1.3]. The transport factors used for the

reference plant in the NUREG/CR-6224 analyses

varied from 0.25 to 0.75, depending on the location

of the break with respect to the floor gratings. The

NUREG/CR-6224 study did not identify methods by

which transport factors can be estimated for other

BWR plants.

The NRC concluded that any engineering judgement

based on a scarce set of experimental data would be

associated with large uncertainties, and therefore,

NUREG/CR-6224 transport factors could not be

defended either as a 'best-estimate' or a 'reasonable

upper-bound estimate'. As a result, while formulating

the Regulatory Guide 1.82, Rev. 2, NRC recommended

usage of 100% debris transport unless lower transport

factors could be justified through analyses or

experiments [Ref. 1.4].

The industry and vendors, represented by the Boiling

Water Reactors Owner's Group (BWROG), have cited

the BarsebAck-2 event data and the ABB Karlshamn

data to argue that transport factors chosen in the

NUREG/CR-6224 study are unrealistically large [Ref.

1.3 and 1.5]. The BWROG suggested that deposition

will likely occur on all free surfaces not just gratings as

assumed in the NUREG/CR-6224 study, and therefore,

transport fractions in the range of 0.10 to 0.25 are more

realistic [Ref. 1.6]. The BWROG pointed out that usage

of overly conservative NUREG/CR-6224 transport

factors might preclude several solutions that are

otherwise sound and cost-effective. They proposed a

small scale test program to study debris retention by

selected drywell structures (e.g., gratings) and to

compile data, which can then be used to derive the

appropriate plant-specific transport factors. Individual

licensees were expected to apply these derived

transport factors to estimate the quantity of debris

transported to the suppression pool [Ref. 1.7]. A

reliable knowledge base would be necessary to judge

the appropriateness of individual licensee assumptions.

The need for such knowledge base was also expressed

by CSNI/PWG International Task Group [Ref. 1.3],

which pointed out that drywell transport is the least

understood aspect of the BWR ECCS strainer issue.

In response to this need, NRC initiated a study,

referred to as drywell debris transport study (DDTS) to

investigate debris transport in BWR drywells using a

bounding analysis approach. This bounding analysis

was to estimate the fraction of debris transported from

the drywell to the suppression pool during blowdown

and washdown phases of a postulated LOCA scenario

in BWRs. The focus of the DDTS is to provide a

'Because debris generated by breaks located in the high region

will have to pass through two floor gratings, a smaller fraction of

them will be transported.

1-1

2 solutions based on active strainers, 100% transport should be

assumed during blowdown which typically lasts a few hundred

seconds.

NUREG/CR-6369
description of the important phenomena and plant

features that control and/or dominate debris

transport during blowdown and washdown, and the

relative importance of each phenomenon as a

function of the debris size. The results of the DDTS

should provide reasonable engineering insights that

can be used to judge the appropriateness of debris

transport factor estimates used in the utility strainer

blockage analyses. The auxiliary guidance provided

by NRC included:

* The study will focus on fibrous debris only.

* The focus should not be to develop a

comprehensive predictive tool that can be

readily applied to plant types and scenarios.

Instead, the study should integrate experimental

and analytical results in such a way that an

engineer familiar with nuclear plants, but not

necessarily an expert in strainer blockage issues,

can comprehend and apply the results.

• The study should use "conservative"

assumptions, if data is unavailable and can not

be generated within the allocated resources or

within schedule.

In parallel, the NRC assembled a Phenomena

Identification and Ranking Table (PIRT) panel to

review the scope of the DDTS, rank the phenomena

of importance, and advise the NRC on the methods

used to analyze each phenomenon [Ref. 1.8].

1.2 Program Overview and Report

Outline

SEA undertook the DDTS with subcontractor

support from Alden Research Laboratory, Inc. (ARL)

in July 1996. From the onset the study focused on

identifying important transport pathways and

phenomena that control or dominate the mode of

transport. The first step of the DDTS was to

undertake an end-to-end scoping calculation to

understand the thermal and hydraulic mechanisms

that govern debris transport and their relative

importance. The study also identified vital data

needs to accomplish the overall objectives. A series

of experiments were designed and conducted to

address the data needs related to inertial capture on

drywell structures and washdown of debris by

ECCS flow. Also, detailed CFD simulations were

undertaken to determine likely flow patterns that exist

on the drywell floor and likelihood of debris

sedimentation. The DDTS relied primarily on this

database to quantify the importance of each transport

pathway.3 Analytical tools (e.g., computational fluid

dynamics codes and MELCOR) were used as needed

either during experiment design to establish thermalhydraulics conditions to be simulated in the

experiments, or in the post-experimental stage to scale

the experimental data to plant conditions. In all cases,

analytical tools were used within their specified range

of applicability and then benchmarked against

experimental data whenever necessary. Figure 1-1

provides an overview of the DDTS.

A simplified logic chart method was chosen to integrate

experimental data and analytical results such that

rationale used to derive the transport factors would be

tractable and easily comprehended. A separate logic

chart was developed for each accident scenario and

each plant type to accommodate differences in plant

conditions that control transport. The logic and

rationale used to quantify the logic tree are

summarized in this report, including a brief

phenomenological description of debris transport in

BWR drywells. This report also summarizes the

phenomena and plant features that were determined to

dominate or control debris transport. Finally, this

report provides an example on how the study results

can be applied to a particular BWR plant.

As noted above, the logic tree quantification relied

mainly on the experimental data obtained as part of the

DDTS. To this end, a total of three experiments were

designed and conducted as part of this study. The first

two experiments focused on studying inertial capture

of debris on typical drywell structures during airborne

transport. The third experiment studied washdown of

debris previously deposited on various drywell

structures by break overflow and containment sprays.

The experiments are described in detail in

NUREG/CR-6369, Supplement 1, "Drywell Debris

Transport Study: Experimental Work" [Ref. 1.9].

In addition, the study relied on analytical models to

quantify phenomena that were: (a) previously studied

experimentally by other investigators [Ref. 1.9] or (b)

amenable to be simulated using existing codes

'Such an approach was determined to provide the best option for

judging appropriateness of plant-specific assumptions. The PIRT

panel input was used to revise some of the elements of the

experimental program.

NUREG/CR-6369 1-2
Figure 1-1. Programmatic overview of the drywell debris transport study.

1-3 NUREG/CR-6369
codes (e.g., Computational Fluid Dynamics code) to

an adequate degree of accuracy. In the former case

analytical models were used to scale the data from

past test facilities to BWR drywells. In the latter

case, analytical models were directly used to

quantify the impact of selected transport

phenomena. These analytical models are

summarized in NUREG/CR-6369, Supplement 2,

"Drywell Debris Transport Study: Analytical Work."

[Ref. 1.10]

1.3 References

1.1 US Nuclear Regulatory Commission,

"Potential for Loss of Emergency Core

Cooling Function Due to a Combination of

Operational and Post-LOCA Debris in

Containment," Information Notice 93-94,

1993.

1.2 Zigler et al., "Parametric Study of the

Potential for BWR ECCS Strainer Blockage

Due to LOCA Generated DEBRIS,"

NUREG/CR-6224, Science and Engineering

Associates, Inc., 1995.

1.3 International Task Group, "Knowledge Base

for Emergency Core Cooling System

Recirculation Reliability,"

NEA/CSNI/R(95)," 1996.

1.5 "Karlsham Tests, 1992. Test Report. Steam

Blast on Insulation Objects," Report: RVE 92-

205, ABB Atom, 1992.

1.6 R. A. Pinelli, "BWR Owner's Group Comments

on August 1994 Draft Report NUREG/CR6224," BWROG-94158, 1994.

1.7 T. A. Green, "Preliminary Design

Consideration for ECCS Suction Strainer

Debris Loading and Head Loss," OG97-025-

161, GE Nuclear Energy, 1996.

1.8 G. Wilson, et al., "BWR Drywell Debris

Transport Phenomena Identification and

Ranking Table (PIRT)," Final Report,

INEL/EXT-97-00984, Lockheed martin Idaho

Technologies Co., Idaho Falls, ID, September

1997.

1.9 Rao, et al., "Drywell Debris Transport Study:

Experimental Work," NUREG/CR-6369,

Supplement 1, SEA 97-3510-A:15, September

1997.

1.10 Rao, et al., "Drywell Debris Transport Study:

Analytical Work," NUREG/CR-6369,

Supplement 2, SEA 97-3510-A:16, September

1997.

1.4 US Nuclear Regulatory Commission, "Water

Sources for Long Term Recirculation

Cooling Following a Loss of Coolant

Accident," Regulatory Guide, 1.82, Rev. 2,

1995.

NUREG/CR-6369 1-4
2. Methodology Overview

2.1 Debris Transport Pathways

A LOCA in a BWR would destroy fibrous insulation

blankets and generates fibrous debris in a region

surrounding the break, referred to as the zone of

influence (ZOI) or the break region [Ref 2.1]. This

debris would be carried away from the break region

by high velocity steam flow, in the case of a main

steam line break (MSLB), and by steam-water

mixtures, in the case of a recirculation line break

(RLB). However, the BWR drywell presents

numerous structural impediments to such a

transport in the form of I-beams, columns, pipes,

floor gratings, instrument panels, etc. Some of these

structures will be wet due to steam condensing on

their relatively cool surfaces and deposition of water

droplets that are produced by the jet expansion

process. Some fibrous debris could adhere to such

structures located outside the break region in spite

of the high steam velocities, which act to shear them

away from the structures. In addition, some fraction

of the debris would enter enclosures (e.g., reactor

cavity) and become trapped. Finally, an additional

fraction of debris would be deposited at the vent (or

downcomer) entrance on the drywellfloor. The

remaining debris would be transported by the

blowdown flows to the vents (or downcomer)1 , and

subsequently to the suppression pool.

Figure 2-la and 2-lb illustrates the physical

processes that govern debris transport through

drywell during blowdown. As shown here, during

and after blowdown debris would traverse over

most regions of the containment and depending on

the local flow and structural surface conditions, they

can be captured in different regions of the

containment. Following blowdown, water would be

introduced into the drywell by break overflow or

drywell sprays2 . Water flow from the containment

sprays cover nearly 100% of the region located

underneath the sprays (see Figure 2-lb). On the

other hand, overflow from the break spreads over a

small cross section of the drywell located directly

beneath the break. In both cases, as the water

cascades down from the location of its introduction

it may washdown (i.e., re-entrain or erode) debris

previously deposited on structures located in its path.

Potential for transport by washdown would be minimal

for debris deposited on structures located above the

containment sprays (referred to hereafter as StructuresAbove) or in enclosures, since they would not be

subject to any water flow (with the exception of

condensate drainage which is minimal). On the other

hand, washdown potential would be largest for the

structures located directly underneath the break

(referred to as Structures-Below) that would be

subjected to break flow (=25, 000 GPM) and

containment spray flow (=4500 GPM). Debris located

on these structures could be eroded in addition to

simply being re-entrained. For other structures

(referred to as Structures-Other), washdown potential

would be moderate as they would be subject to

containment sprays only.

The washed down debris would be brought down to

the drywell floor where water accumulates to form a

pool until the water level rises above the vent entrance

(see Figure 2-lb). The pool height and the flow

dynamics, including the turbulence levels, are highly

plant-specific, controlled by such features as the water

flow rate, height from which water falls into the pool,

vent pipe offset from the floor and type of structures

located close to the floor. Depending on the pool

dynamics, the debris brought down by water may

remain in suspension or may settle down. The pool

dynamics may also re-suspend some of the debris

previously deposited on the drywell floor (e.g. near

vent entrances). The pool height and flow dynamics

within the pool are highly plant-specific. The fraction

that remains in suspension would be transported to the

vents as the water overflows into them.

Figure 2-2 delineates the transport pathways and the

close coupling that exists between blowdown and

washdown transport processes described above. The

quantity of debris advected to the vents due to the

combined effects of these pathways can be expressed as

[Ref. 2.1]:

Vpool = F * Vgen (2-1)

' This study assumes that all of the debris entering the vents

would be transported to the suppression pool.

2 Type and duration of water flow are plant specific. In some

scenarios water may not enter the drywell.

2-1 2-1 NUREG/CR-6369
Methodology Overview

Structures

Above Top of Shield Wall

Structures

\rBreak

~Drywell Pool

A. Blowdown Phase

B. Washdown Phase

Figure 2-1. Postulated debris transport pathways in a Mark I BWR.

NUREG/CR-6369 2-2
Methodology Overview

Figure 2-2. Transport pathways in a BWR.

2-3 NUREG/CR-6369
Methodology Overview

where,

Vigen is the volume of ith size fibrous debris

generated in the drywell break region

(ft3 )

pool is the volume of ith size fibrous debris

transported to the suppression pool (ft3 )

Fi is the drywell debris transport factor for

the ith size debris.

The objective of this study is to estimate Fi for three

different types of BWR drywell designs (Mark I, II

and III) and for several postulated accident

scenarios.

As shown in Figures 2-1 and 2-2, transport occurs

over two distinct phases of accident progression, the

blowdown phase and the washdown phase. Hence,

Fi can be expressed as:

down. Thus, the problem of estimating the total

transport factor, Fi, can be seen to be decomposed into

the following parts:

1. Estimate fractions of the fibrous debris deposited

on (or trapped by) enclosures, structures-above,

structures-below, structures-other, and drywell

floor (i.e., Xienc, X'sa, Xisb, Xis, and X'df). These

fractions are referred to as capture fractions

hereafter. The remaining fraction (Fibd) will be

advected to vents during short-term blowdown.

2. Estimate fractions of the debris deposited on (or

trapped by) each structural class that would be

washed down during long-term ECCS recirculation

phase (i.e., Y'sa, Y'sb, and Yi5o). These fractions are

referred to as washdown fractions. This fraction of

the debris previously deposited on the structures

during blowdown would reach the drywell pool,

where as the remainder will remain permanently

on the structures.

3. Estimate fraction of the debris reaching the

suppression pool that would remain in suspension

and would be advected to the vents during longterm ECCS recirculation phase (Zi). The remainder

will settle down on the drywell floor.

Decomposing the problem into these three parts avoids

the need for conducting integrated analyses that tend

to be very complex. Such decomposition also allows

for designing experiments and conducting analyses

specifically applicable to each part.

2.1.1 Blowdown Transport (Short-term)

F= Fbid + Fwd (2-2)

Fi bd and Fi wd are blowdown and washdown

transport factors, respectively. The blowdown

transport factor can be decomposed as follows:

Fi l Id_( sb so df

Fbd = 1 - e. -s X A sXb - Xo - XAdf (2-3)

Where, X ien, X'sa, X'sb, Xiso and Xisf are fractions of

generated debris deposited on (or trapped by)

enclosures, structures-above, structures-break, structures

other and drywellfloor, respectively. On the other

hand, the fraction transported during long-term

washdown phase, Fiwd, can be expressed as:

Fwd = FFloor .Z (2-4)

FiFloor is the fraction of the generated debris that

would reach the drywell floor and Zi is the fraction

of that debris that remains in suspension and is

ultimately transported to the vents. FiFIoOr can be

further expressed as:

F~Io = Xi . yi i ., i i, 1. X i 

Floor sa sa +Xsb Ysb +X50 Ys. +Xdf

(2-5

Yisa/ Y'sb, and Yiso are the fractions of ith size debris

previously deposited on structures-above, structuresbreak and structures-other that would be washed

Transport of debris from the break region to the vents

by blowdown flow is referred to as blowdown

transport or short-term transport.3 This transport is

controlled strongly by the transport medium (i.e., the

continuum that entrains debris particles). Depending

on the break type (i.e., main steam line break or

recirculation line break), a fraction of the generated

debris would be transported by the steam flow and the

remaining fraction would be transported by the water

component. For example, in the case of a main steam

line break, the break effluent is primarily steam with

equilibrium quality greater than 0.9, and void fraction

close to 1. As a result, blowdown debris transport in

5) this case is driven entirely by bulk movements of the

gaseous phase. In the case of a recirculation line break,

'This is because blowdown transport occurs over a short time scale

(within minutes) after a LOCA.

NUREG/CR-6369 2-4
Methodology Overview

large quantities of water is introduced into the

containment. In this case, a fraction of the debris

would be entrained by the steam flow, whereas the

remaining fraction is carried by the water

component. Section 4 presents the rationale used to

partition the debris according to the medium in

which it is transported.

Transport by the Gaseous Phase

Estimation of the capture fractions (i.e., Xienc, Xsa,

Xisb, Xis,, and Xidf) associated with vapor phase

transport requires information related to the

following quantities:

1. The fraction of the generated debris carried

into the enclosures, structures-above, structuresbreak, structures-other and drywellfloor.

2. Efficiency (or effectiveness) of the structures

located in each of those regions to trap or

capture debris.

The fraction of debris transported into each region

depends on the bulk flow patterns established in the

drywell as a result of blowdown from the break and

the relief provided by the vent pipes. A variety of

analyses, including MELCOR4 and CFD calculations,

were performed to predict drywell flow patterns

following postulated recirculation and main steam

line breaks [Ref . 2.2 and 2.3]. Break blowdown flow

velocity, temperature and quality, required as input

to these calculations, were obtained based on RELAP

simulation of BWR/4 plants. Additional input

related to structural layout and bulk porosity was

gathered from detailed surveys of Mark I and Mark

II drywells [Ref. 2.2]. Results of these calculations

coupled with engineering judgments' were used to

estimate the fractions of debris advected into each

region of the drywell. Section 4 summarizes the

important results of these analyses and how they

were used.

The results of the analyses concluded that high gas

velocities (25-100 ft/s) outside the break region

would entrain and transport insulation debris

through the drywell unless it is trapped (or

captured) by structures located upstream6 . Inertia will

cause the fibrous debris to impact structural objects

located in fibrous pathway. The majority of the time,

these structural impediments will be wet due to steam

condensation and water droplet deposition on their

surfaces. However, it was not clear if the debris

particles thus impacting the structures would adhere to

those surfaces or be sheared off by the high gaseous

velocities. Debris larger than the clearance (4" x 11/1⁄2")

in the floor grating would be trapped on the floor

grating. It was not known if such pieces would remain

on the gratings or be forced through the gratings by

gaseous flow later on. Two experiments were

conducted to gain a basic understanding of capture on

drywell structures:

1. The separate effects tests focused on measuring

removal efficiency of isolated structural elements

placed in a test channel and subjected to plug

flow of air intermixed with debris particles of

known size. The structures were wet by water

sprays to the desired wetness covering a wide

range of conditions anticipated in the drywell.

The debris were injected uniformly into the flow

stream by a debris injection gun. The structures

examined included the Mark II vent pipe, pipes,

I-beam, and floor grating. A brief overview of

the test program and its results are summarized

in Table 2-1. The experiments also studied

potential for degradation of large insulation

pieces that are trapped on structures, such as

floor gratings, when subjected to remaining

blowdown flow at a velocity of 150 ft/s.

2. The integrated effects tests were conducted in

which insulation debris generated by 1100 psi jet

from a 4" nozzle were transported over

structural elements assembled to the

prototypical congestion level. In these tests, an

aged insulation blanket was mounted on a target

pipe located in the center-line of the jet

expanding from the nozzle. The debris were

then allowed to be transported across the

structural region. A comprehensive survey of

BWR containments was used to design this

structural region, which is 20 ft long. Full scale

structures such as I-beams, pipes, floor gratings,

and Mark I vents were simulated. The measured

4 MELCOR was used primarily to estimate time taken for vent

clearing in Mark I and Mark II drywells and to establish

appropriate boundary conditions for CFD analyses.

'Engineering judgements were necessitated by the fact that all

these analyses (including MELCOR and CFD simulations) sought

several simplifying assumptions to minimize computational

effort.

6 Larger partially torn insulation blankets will become de-entrained

under the influence of gravity. They are not included in the

following discussions.

2-5 NUREG/CR-6369

Methodology Overview

capture efficiencies were compared with

separate effects tests (after properly scaling

them). Table 2-2 presents an overview of the

experimental program and important findings.

These experiments were designed to be more

prototypical of BWR conditions following a

LOCA.

The experimental program is described in detail in

NUREG/CR-6369, Supplement 1 [Ref. 2.4]. The

program provided a knowledge base that can be

used to judge the effectiveness of various structures

to capture debris as a function of structured wetness,

flow velocity, and debris size. This knowledge base

was coupled together with analytical models and

engineering judgment to estimate fraction of the airborne debris deposited on various structures.

Figure 2-3 summarizes all of the data gathered and

used to quantify X'en, Xisa, X'sbX'so and Xidf..

Transport by Liquid Phase

A fraction of the generated debris would be

entrained and transported by water flow during the

early stages of a postulated recirculation line break.

CFD calculations have shown that due to drag

imparted by the surrounding structures, break water

spreads over a limited cross-section of the drywell

[Ref. 2.3]. If it is assumed that water spreads over a

quarter of the drywell cross-section, the resulting

flow (approximately 50-200 GPM/ft2 ) will impart

sufficient drag on the debris located in its pathway

and transport them to the drywell floor7 . The only

exception will be pieces larger than the grating

clearance of 4"xl.5" which will become trapped on

the gratings. As a result, a simple model was used

to quantify short term capture fractions (i.e., Xiend,

Xisa, X'sb , X 0so and X'df) associated with liquid phase

transport.

2.1.2 Washdown Transport (Long-term)

Structural Washdown

Transport of debris deposited at different locations

in the drywell by ECCS water flow occurs over a

long-term (up to hours). If the debris is loosely

attached to the structures, it may simply be reentrained and carried to the bottom of the drywell. If

the debris is trapped, it may erode with time when

'This conclusion was further verified by the tests described in the

following sections.

subjected to water, with the secondary debris

generated by erosion brought to the drywell floor.

In order to estimate structural washdown fractions

(i.e., Yisa, Y'sb and Yis o), knowledge of the following

phenomena is necessary:

1. Distribution of debris in the drywell at the

end of blowdown,

2. Type of debris and its mode of attachment to

the structures8 ,

3. Assumptions related to ECCS operation (i.e.,

ECCS response), and

4. Potential for washdown and erosion for each

debris size as a function of water flow to

which it is subjected, duration of exposure

and the structure to which it was attached.

As shown in Figure 2-4, distribution of debris at the

end of blowdown, type of debris and their mode of

attachment were determined from analyses

described in Section 2.1.1. Utility Final Safety

Analysis Reports (UFSAR), Emergency Operating

Procedures (EOP) and simple engineering analyses

were used to determine the duration of flow and the

location of flow. Finally, experiments were

conducted to determine if pieces of various size

debris located on drywell structures could be

washed down or eroded down when subjected to

water flow. Table 2-3 provides an overview of this

test program conducted at SEA. These analyses and

experiments were coupled together to derive Yisa,

Y1

sb and Y'5 0 in Section 4 for each accident scenario.

Sedimentation in the Drywell Pool

The ECCS flow and the washdown debris would be

transported to the drywell floor (see Figure 2-1),

where they form a pool whose depth depends on the

vent-pipe offset height. Transport of debris in the

drywell pool depends to a large extent on the pool

flow-dynamics, pool turbulence levels, debris

characteristics and drywell floor layout. The pool

flow-dynamics would be controlled by the amount

of water added and the height from which it falls

into the pool. The DDTS relied on CFD simulation

of flow on the drywell pool to predict pool flowdynamics corresponding to containment sprays and

break overflow [Ref 2.2]. PP&L flume test data [Ref.

2.5] were used to determine flow conditions that

'For example small debris are loosely attached to the structures

and could be easily washed down. Large debris cannot be easily

washed down from the floor gratings where they are trapped

2-9 NUREG/CR-6369

Methodology Overview

< LOCA_

* Break Type

* Break Location

* Break Size

* Break Flow

Debris Generation

* Size and Characteristics

* Duration Of Generation

* Debris Wetness

Liquid Phase Transport

~. (Recirc. Only)

Vapor Phase

Transport

* Drywell Layout

- Type

- Structures

• Vent Clearing

l Wetness/Condensation

* Bulk Flow Patterns

I

* Gravitaional

* Inertial Capture

* Dispersion

* Filtration

Tools Used:

* Review of drawings for

Mark I, II and III for

possible locations of

severe LOCA breaks.

* RELAP to estimate

break flow (RL &

MSL)

Results:

* Selected RLB and

MSLB for analysis.

* Focus on breaks located

in the drywell

midregion to maximize

debris generation

* RELAP break flows as

input to calculations on

debris generation and

drywell thermal

hydraulics conditions

Tools Used:

* Review of experimental data,

data to identify typical debris

sizes of importance

* Bench-top experiments to

determine likely debris

wetness.

Results:

* Debris falls mainly in 3 sizes

with respect to grating

clearance: small, large, and

large-canvassed (Table 2-1).

* Debris produced by MSLB

likely to be nearly dry

* Debris produced by RLB likely

wet (during water blowdown)

and partially wet (during twophase blowdown)

* Usage of dry debris overestimates transport factor.

Tools Used:

* Survey of BWRs to identify types of

structures and levels of congestion.

* CFD analyses to estimate likely bulk

flow patterns

* MELCOR analyses to estimate likely

structural wetness and time for vent

clearing

* MELCOR analyses to estimate drywell

pool formation and turnover in the case

of RLB.

Results:

* Drywell layouts too complex to be

modeled in a full-scale CFD run.

Several different CFD runs should be

used to determine likely bulk flow

patterns. Outside break region, flow

velocities range between 25-150 ft/s

* Structures will be wet with film

drainage with in 2 seconds after LOCA

due to condensation.

Tools Used:

* Separate effects experiments

to determine capture

efficiency on selected

drywell structures of variable

congestion.

* Integrated effects experiments to determine eff. of

drywell structures at typical

congestion levels.

* CFD runs to estimate

potential for settling.

Results:

* Gratings provide largest

potential for debris capture.

. Pipes and I-beams possess

low removal efficiency

* Turbulence levels are too

high to allow debris settling

* Surface wetness plays a key

role in debris capture.

Figure 2-3. Data gathered to evaluate drywell debris transport during blowdown (short-term) phase.

NREG/CR-6369 2-13
Water Phasel

Break Flows I

Break Over-Flow

Condensate

Drainage

C

0

u0

C)

M

12

X

en

0

U)

cu

-- -Structural Washdown - _ Drywell Floor

.Pool Transport

Methodology Overview

Containment

Sprays

* Debris Distribution

and Attatchment

* Flow Rates

* Debris Type

* Erosion

* Floor Layout - Mark 1, 11 & Ill - Vent Off-Set

* Debris Characteristics

* Pool Flow Patterns

* Pool Turbulence

Tools Used:

* RELAP Runs to estimate waterphase blowdown.

* FSAR and EOP review to identify

sources of water in postulated

accident scenarios. Flow rates and

duration critical.

Results:

* Break blowdown water not

sufficient to overflow Mark III

drywell pool.

* Systems response strongly

dependent on accident scenario

and operator action. Assume

conservative numbers to bound

significant plant-specific

variations.

* Break overflow unlikely following

MSLB

* Containment spray unlikely after

RLB.

Tools Used:

* Input from Blowdown calculations to estimate

debris distribution at the end of blowdown.

* Engineering judgements and CFD runs for

flow distribution on various structures

* BWROG experimental data on debris size.

Enhanced with NRC experiments.

* NRC washdown experiments for structural

washdown of small pieces and erosion of large

debris.

Results:

* Assume that break overflow uniformly spreads

over the structures located in the quadrant in

which break is located.

* The containment sprays can washdown large

fraction of small debris on gratings.

* The condensate drainage has little impact on

transport.

* Break flow can washdown small debris and

erodes large debris. Erosion time-dependent.

Tools Used:

* Plant drawings for Mark 1, 11 and III

drywells for layout and vent design

details.

* CFD runs to interpret previous

existing data: PP&L Flume Transport

data.

* BWROG Data.

* CFD runs simulating flow on drywell

floor for Mark I, II and III

containments corresponding to break

overflow and spray.

Results:

* Mark II pools are turbulent during

spray and break operation. Likely

transport during both scenarios.

* Mark I and Mark III pools allow for

debris settling in the case of spray

operation. Break overflow induces

enough turbulence to transport 100%

of debris.

Figure 2-4. Data gathered to evaluate drywell debris transport during washdown (long-term) phase.

2-14 NUREG/CR-6369

Methodology Overview

would be necessary to entrain different size debris.

The information from these two steps was coupled

to evaluate the potential for transport of

small and large debris in Mark I, II and III drywell

pools formed by drywell sprays and break overflow.

Table 2-4 provides an overview of the analyses

conducted and the important findings. Details of

these analyses are documented in NUREG/CR-6369,

Supplement 2 [Ref. 2.2].

2.2 Debris Size Considerations

From the onset, the study was designed to identify

dominant transport pathways and the associated

transport fractions as a function of the size of the

debris. Such an approach was necessitated by the

fact that debris size distribution that is universally

applicable to plant conditions and accident scenarios

is not available. On the other hand, there is

consensus that the debris can be broadly divided

into three size classes: small9 , large, and largecanvassed, according to their relative size and

pathways available for their transport. Figures 2-5,

2-6, 2-7, and 2-8 are the photographic images of the

typical small, large, and large-canvassed pieces

studied. All experiments and analyses were

designed to compile a knowledge base for all three

size groups. Based on the insights gained from these

experiments, the larger pieces are further divided

into two groups according to the location of their

generation with respect to the lowest major floor

grating: large-above and large-below. This

classification reflects fundamentally different

pathways associated with each size group. Table 2-5

provides a brief description of the debris, their

geometrical range and associated transport pathway.

As noted in Table 2-5, the large-canvassed pieces

were found to be "non-transportable" and hence

were screened out from further analysis.

2.3 Identification of Controlling

Phenomena and Plant Features

Experimental data were analyzed together with

information related to expected plant conditions to

'It should be noted that, initially, efforts were made to further

classify small debris into sub-groups fines, small and medium

consistent with NUREG.CR-6224 study [Ref. 2.1]. However, a

decision was made to collapse them into a single group called

small because: a) fines, small and medium pieces have very

similar transport pathways and b) existing debris size

distribution data does not differentiate these three size groups

[Ref. 2.3].

identify controlling phenomena and plant features.

The study suggests that the number and

arrangement of floor gratings, duration of ECCS

flow, and drywell floor layout (including vent

design) are the key plant features that control

transport. Another parameter that can significantly

influence transport fraction is the debris size

distribution. The most important transport

pathways are:

* Advection of small debris during blowdown,

* Advection of large debris generated below

lowest floor grating during blowdown, and

* Erosion of large debris captured on gratings,

and

* Gravitational settling of debris in drywell

pools when subjected to containment spray.

Section 3.0 provides further details on these

pathways.

2.4 Debris Transport Factor

Quantification

As evident from the previous discussion, the fibrous

debris transport is a complex process involving

several competing phenomena. Development of a

comprehensive "best-estimate" predictive tool that

accounts for each phenomenon mechanistically was

beyond the scope of this study". Instead, the study

decomposed the problem and studied each transport

pathway shown in Figure 2-2 independently. The

experimental data and analytical predictions

compiled for each transport pathway were

integrated together using simplified logic trees.

These logic charts were structured based on insights

gained regarding important transport pathways for

each debris size category. Figure 2-9 presents a

generic logic tree used to quantify debris transport,

including definitions of various terms. As shown in

Figure 2-9, the logic chart decomposes the problem

into five independent steps: LOCA Type; Debris

Classification, Distribution after blowdown, Erosion

and Washdown; and Sedimentation in drywell pool.

The first column describes the accident being

analyzed. This information sets the boundary

conditions for all the subsequent steps. The second

column specifies the size distribution data through

the use of size fractions (il l, T12, 713, and 114) defined

as the mass fraction of the debris belonging to size

classes small, large-above, large-below and large-

' Also, see NRC guidance listed in Section 1.

2-17 NUREG/CR-6369

Methodology Overview

Figure 2-5. A photograph of small size insulation debris produced in air-jet tests.

Figure 2-6. A Photograph of Large Size Insulation Debris Produced in Air-Jet Tests

NUREG/CR-6369 2-21
Methodology Overview

Figure 2-7. A Photograph of Large Canvassed Debris Produced in Air-Jet Tests

Figure 2-8. A Photograph of Shredded Canvassed Debris Produced in Air-Jet Tests

NUREG /CR-6369 2-22
Methodology Overview

Table 2-5. Debris classification.

Debris Type Dimensions NUREG/CR-6224 Transport Characteristics

Terminology

Small <6" x 4" Classes 2-6 * Smaller than (-equal to) grating clearance. Will be

(Figure 2-5) forced through gratings

* Gravitation settling negligible

* Vent capture unlikely

. Pool turbulence can keep them in suspension

. Washdown by sprays and break flow

Large > 6"x4" 6+ . Unlikely to be forced through grating even at flow

(Figure 2-6) velocities >200 ft/s.

* No washdown by sprays

. Erosion by break flow

* Capture at vents

Large- >6"x4" "Non- . Transport unlikely

Canvassed covered with transportable" * No pathway for transport identified

(Figure 2-7) canvas

Canvas 1"xl" to 3"x3" Not considered . Same as small

Fragment

(Figure 2-8)

NUREG/CR-6369 2-23

Methodology Overview

example was provided to illustrate how such information

can be folded-in to calculate a single transport factor that

can be used to estimate the quantity of debris reaching the

suppression pool, provided the quantity of insulation

contained in the zone of influence is known.

The next three steps allow the user to enter data regarding

inertial capture of debris on drywell structures located in

various regions of the drywell, the fraction of that debris

that would be eroded and washed down by water flow,

and subsequently, the potential for sedimentation of

debris on the dryweU floor. Data on capture fractions

(Xjieny X idf' X isa' X isb and X iso), washdown fractions I

(Y isa' Y isb' and Y iso) and drywell pool transport

fraction (Zi) applicable to each postulated accident

scenario were derived and entered in these three columns.

Section 2.1 provides definitions of each term, with the

rationale for their quantification provided in Section 4.

The entries under heading 'Fractions' were obtained

simply by multiplying the branch fractions associated

with that particular pathway. The fractions whose final

location is vents were then added to calculate the 2.

transport factor for the accident scenario being evaluated.

Six different types of transport factors were derived from

this study:

Fl Fraction of small debris transported to the vents

F Fraction of large-above debris transported to the

vents

F b Fraction of large-below debris transported to the

vents

F large Fraction of all large debris transported to the vents,

defined as (r12*F + i139 F b)/(1r2+113)

F trans Fraction of 'transportable debris' transported to

the vents, defined as (T1Fs+`l2* F

1

a + rl3e

Flb)/(Tll1+2+-q3)

Fzo[ Fraction of all the debris contained in the ZOI

that would be transported to the vents, defined

as (l1Fs+`12o F la + T3o Flb)

These six transport factors were derived for each accident

scenario. The calculated transport factors were found to

be a strong function of the accident scenario assumed. A

separate logic tree was developed for each accident

scenario that analyzed impact of variations in the

following parameters:

* Plant Design

* Break Type and Location

* ECCS Throttling

* Containment Spray Operation

Figure 2-10 provides a complete spectrum of accident

scenarios analyzed in the present study

For each of the twenty (20) scenarios analyzed (see Figure 2-

10), two types of estimates for debris transport fractions

were obtained:

Upper Bound Estimate. These estimates were obtained

by compounding bounding estimates for each individual

logic-tree branch. It is unlikely that actual drywell

transport factor in a BWR following a LOCA would be

greater than the upper bound estimate. The upper bound

estimates can be treated as generic estimates that will

most likely bound all accident scenarios and operating

conditions for that plant type.

Central Estimate. These estimates were obtained by

compounding more realistic estimates for each individual

branch. The central estimates are judged to be closer to

reality, but without the assurance that they can not be

exceeded under any accident condition. Central estimates

should be applied on a plant-specific basis after assuring

that actual plant systems behavior is consistent with the

accident scenarios analyzed and that the underlying

modeling assumptions are representative of the particular

plant.

Appendix-A contains a complete listing of all the logic trees

developed in this study. In addition, Section 4 describes the

quantification process in detail by considering logic trees

developed for two postulated breaks. Section 5 provides an

example of how the results of the present study can be

integrated with the debris size distribution data to estimate

combined generation-transport factor.

As discussed above, a total of 20 accident scenarios were

analyzed as part of the DDTS (see Figure 2-10), which

considered variations in the following parameters (or plant

data).

2-27 NUREG/CR-6369
Methodology Overview

Initiating Event Plant Design Type of Break Throttle ECCS Flow Operate Containment Sprays

Chart of LOCA Scenarios Analyzed 0 erated Intermittently

in Debris Transport Study Yes (Steaming)

LNot Opreated

Main Steam Line Break I o erated Intermittently

No (Full Flow c 1 Hr.

Mark I Containment Not preated

O erated Intermittently

Yes (Full Flow < 1 Hr

NotO Oreated

Recirculation Line Break

l erated Intermittentil

No (Full Flowc3 r l

Notp reated

O erated Intermittently

Yes (Steaming) I Not 0 reated

Main Steam Line Break

Scenarios Analyzed 0 erated Intermittently

No (Full Flow c1 hrl l

Mark 11 Containment lNot reated

O erated Intermittently

Yes (Full Flow < 1 Hr

NotO Oreated

Recirculation Line Break

O erated Intermittently

No (Full Flow < 3 hr.

Not 0 reated

Yes (Steaming)

Main Steam Line Break

No (Full Flow c 1 hr.)

Mark Ill Containment Yes Full Flow < 1 Hr)

Recirculation Line Break

No (Full Flow < 3 hr.)

Figure 2-10. Accident scenarios analyzed in the study.

2-28 NUREG/CR-6369
Methodology Overview

2.4.1 Plant Design

Drywell transport factors were derived for all three

types of drywell designs: Mark I, II, and III. Plant

features that are most common" were used to define

generic design of each containment type. For

example, each containment type was assumed to

contain two levels of contiguous floor gratings"2.

Major differences between these containment types

as modeled in the study pertained to vent

arrangement and ECCS flow rates. These differences

were found to significantly impact debris transport

during washdown. Other differences between plant

types were found to be of secondary importance

(e.g., containment volume, structural congestion

level) and hence were modeled generically.

2.4.2 Selection of Break Type and Location

For each containment type, two breaks were

analyzed:

1. A double ended guillotine break in the main

steam line with full separation of broken ends

in the mid-region of the drywell

2. A double ended guillotine break in the

recirculation line with full separation of

broken ends in the mid-region of the drywell

Breaks can occur in the main steam lines,

recirculation lines or feedwater lines, all of which are

pressurized during normal operation. In this study,

breaks in feedwater line were screened out as they

were found to have been bounded by postulated

breaks in the recirculation lines.

The location of an arbitrarily postulated main steam

line (MSL) breaks may vary from the top of the

containment where the MSL enters the biological

shield to the mid-region where the MSL exits the

drywell. Recirculation line break locations can vary

from the bottom of the drywell (close to the drywell

floor) to the mid-region where the recirculation flow

enters/exits the pressure vessel. Examination of

drywell piping layout would demonstrate that

breaks located in the mid-region of the drywell will

subject more target pipes (i.e., insulated primary

" A comprehensive survey of BWR drywells was used to identify

most common plant features for each plant type with special

emphasis on number and arrangement of floor gratings.

" Survey indicates that several Mark II drywells contain more

than two levels of grating, whereas several Mark Is contain only

one grating. Such plant-specific variations can be easily

accommodated by modifying appropriate logic trees, as shown in

Section 5.

pipes) to higher pressures than the breaks postulated in

either extremes of the drywell. Therefore, it is very

likely that breaks located in the mid-region of the

containment would generate substantially more debris

than other postulated locations. As a result, the study

focused on the breaks postulated in the mid-region of

the drywell'3 .

2.4.3 ECCS Throttling

In addition to ECCS flow rate, duration of unthrottled

ECCS flow also impacts overall debris transport

fraction. Transport fractions were derived for throttled

and unthrottled conditions. While using the results, it

should be noted that throttled ECCS operation is the

most likely scenario, and unthrottled conditions occur

only because of either an operator error or instrument

malfunction.

For a MSLB, throttled conditions assume that the

operator throttles ECCS flow after the reactor core is

refilled, but before the pressure vessel is completely

filled and water starts to overflow through the break.

Unthrottled condition, on the other hand, assume that

the operator does not throttle ECCS flow and lets it

overflow through the broken pipe for an hour after a

LOCA. Similarly, in the case of a recirculation line

break, throttled condition corresponds to throttling

ECCS flow one hour after a LOCA and unthrottled

condition assumes continuous operation of ECCS at full

flow for three hours.

2.4.4 Drywell Spray Operation

Drywell spray operation in the majority of drywells is a

manual function, initiated as a response to high

containment pressure and/or high containment

temperature. Typically, containment sprays are turned

on after ECCS flow is throttled, and are operated

intermittently for up to 30 minutes at a drywell time.

Some of the containment designs do not possess sprays.

For Mark I and II designs, the impact of intermittent

operation was quantified assuming 30-minute

operation. Mark III containments either do not possess

drywell sprays, or are not likely to operate them.

2.5 References

2.1 Zigler et al., "Parametric Study of the Potential

for BWR ECCS Strainer Blockage due to LOCA

13 However, the logic charts were structured to accommodate breaks

in other regions of the drywell by simply varying i2, and 3.

NUREG/CR-6369 2-29
Methodology Overview

Generated Debris," NUREG / CR-6224,

Science and Engineering Associated, Inc.,

1995.

2.2 D. V. Rao and C. J. Shaffer, "Drywell Debris

Transport Study: Calculational Work Final

Report," NUREG / CR-6369, Supplement 2,

Science and Engineering Associates, Inc.,

1997.

2.3 K. Williams, "Simulation of a BWR Drywell

Flow in Response to a Recirculation -Line

LOCA using a Computational Fluid

Dynamics (CFD) Code," FSS Report: RX-96-

05, Flow Simulation Services, Inc., 1996.

2.4 D. V. Rao et al, "Drywell Debris Transport

Study: Experimental Work Final Report,"

NUREG / CR-6369, Supplement 1, Science and

Engineering Associates, Inc., 1997.

2.5 P. Murthy and M. Padmanabhan, "ECCS

Strainer Model Study: Transport and

Experimental Studies in a Laboratory Flume,"

Report 31-94/M216F, Alden Research

Laboratory, Inc. 1994.

2-30 NUREG/CR-6369
3. Controlling Phenomena and Plant Features

One of the objectives of the DDTS is to identify

physical phenomena/processes and plant features

that control and dominate insulation debris

transport in the BWR drywell. Experimental data

were used to draw the necessary insights.

3.1 Controlling Plant Features

Three plant features that control debris transport

are: (1) number and arrangement of gratings with

respect to the break, (2) vent and drywell floor

design, and (3) duration of unthrottled ECCS flow.

3.1.1 Effect of Floor Gratings

Experimental data clearly illustrate that drywell

floor gratings provide the largest potential for

capture of both small and large debris. Figure 3-1

illustrates capture of small debris on wet floor

gratings. The measured capture efficiencies varied

between 15% and 30% for small debris depending

on the flow velocity and relative wetness. But a

large fraction of the captured small pieces will be

washed down within 30 minutes by containment

sprays or within few minutes by break overflow; no

washdown is expected in the case of condensate

drainage.

In the case of large pieces, the floor grating possesses

a capture efficiency of 100%. Figure 3-2 illustrates

the capture of large debris on grating. As shown

here, the large debris are captured on the surface

and cannot be forced through the grating by either

blowdown flow or washdown flow. The only

mechanism available for its transport is erosion by

ECCS flow.

Credit for capture on floor grating should be given

subject to the following considerations:

1. Capture of small pieces is only possible if the

grating surface is wet. Experiments

demonstrated that capture efficiency of gratings

for small debris are small (6%) if the grating

surfaces are not wet'.

2. If floor gratings do not cover the entire flow crosssection they may not be as effective at debris

capture. A survey of the plants suggest that

typically one or two floor gratings exist in each

plant. In some cases, they cover only a small

fraction of the flow cross section and would allow

debris to bypass. Other examples include large

open holes in the gratings designed to

accommodate control valves and piping runs. In

all such cases care must be taken to ensure that

gratings still provide an effective geometry for

capturing debris.

3. Combined effects of blowdown and washdown

should be considered. For example, smaller debris

captured on the grating during blowdown can be

washed down by sprays and break flow.

3.1.2 Vent and Drywell Floor Design

Experiments were conducted to study the effectiveness

of the vents to capture debris. In Figure 3-3, the test

setup used to simulate Mark II vents is shown. As

shown here, the captured debris was deposited around

the vent on the floor or vent plate. These experiments

showed that capture at the vents is a significant

contributor for removal of small, and large pieces; with

an efficiency of 10-15% for small and greater than 30%

for large pieces.2 . However, in order to take credit for

debris capture at the vents, the analyst must carefully

consider combined effects of blowdown and

washdown (i.e., pieces deposited during blowdown

may become re-suspended and transported during

washdown depending on the hydrodynamic conditions

that exit in the pool during washdown phase).

A pool of water that formed on the drywell floor may

provide an area where debris might settle during

washdown. Analyses conducted as part of the study

suggest that significant debris retention might be

possible in the pools formed during spray operation.

On the other hand, the potential for debris settling is

low in pools formed of break overflow because such

pools are associated with higher flow velocities and

' In the case of dry grating, filtration of small pieces by large

pieces already deposited on grating is also a possible mechanism

for debris removal. At the concentration of present interest its

contribution is minimal.

2 In case of recirculation line break potential for debris capture at

vents during blowdown could be higher. However, these pieces

may become resuspended and advected during washdown.

3-1 NUREG/CR-6369
Controlling Phenomena and Plant Features

Figure 3-1. Typical small debris deposition on wet gratings observed in the experiments.

NUREG/CR-6369 3-2
Controlling Phenomena and Plant Features

Figure 3-2. Capture of large debris on dry/wet gratings.

(The piece is being subjected to 150 ft/s air flow.)

3-3 NUREG/CR-6369
Controlling Phenomena and Plant Features

Figure 3-3. Capture of small debris around simulated Mark II vent.

NUREG/CR-6369 3-4
Controlling Phenomena and Plant Features

drywell floor can be very effective at retaining debris

on the drywell. Further discussions are provided in

Section 4 with details provided in NUREG/CR-6369,

Supplement 2 [Ref. 3.1].

3.1.3 Duration of Unthrottled ECCS

Operation

Assumptions related to duration of ECCS operation

at full flow following a LOCA play a vital role in

debris transport. Figure 3-4 presents photographic

illustration of large debris erosion by break flow.

Also shown in Figure 3-5, erosion was found to be a

constant rate process [Ref. 3.2]. If the ECCS is

allowed to operate at full flow for several hours after

a LOCA, it is likely that a large fraction of insulation

will be eroded and transported to the suppression

pool. As a result, the debris transport factor may

vary considerably depending on the assumptions

related to ECCS operation. In view of this

variability, results of the present study were

expressed as a function of assumed ECCS response

following LOCA. The analyst should select most

appropriate accident scenario applicable to the plant

under consideration.

3.2 Dominant Transport Processes

The following physical processes/phenomena were

determined to be controlling transport.

3.2.1 Small Debris

Table 2-5 and Figure 2-5 presented a description of

small debris. Typically, a majority of this debris is

smaller than the grating clearances and can readily

pass through them. Analyses and experiments

suggest that small debris possess low gravitational

velocities (1-3 ft/s in air STP), and tend to stay fully

suspended at airflow velocities higher than 10 ft/s

(see Section 2.4.1 of Ref. 3.2). The processes that

dominate transport of small debris are: advection,

inertial capture, washdown and pool

hydrodynamics. During blowdown the gratings are

the most likely locations for debris capture, followed

by other structural congestion, vents and drywell

floor. For Mark I and III containments, the most

dominant transport pathways for small debris are:

1. Advection during blowdown by steam/water

mixtures

2. Washdown of pieces previously deposited due

to inertial capture by break flow and subsequent

advection to vents.

For Mark II containments, the dominant transport

mechanisms are slightly different:

1. Advection during blowdown by steam/water

mixtures

2. Washdown of pieces previously deposited

due to inertial capture by spray flow and

subsequent advection to vents.

3. Washdown of pieces previously deposited

due to inertial capture by break flow and

subsequent advection to vents.

Other transport pathways were found to be of

secondary of importance.

3.2.2 Large Debris

Experiments were conducted to study if large pieces

would be forced through the grating clearances due

to: (a) exposure to high velocity steam flow, (b)

exposure to high velocity two-phase jet flow typical

of recirculation line break, or (c) prolonged exposure

to break/spray water flow. The results suggest that

large pieces (1 /8th or higher in thickness) exposed for

several minutes to 150 ft/s3 airflow neither erode nor

are forced through the grating, although pressure

drop across the pieces is as large as 0.5 -1 psi 4

.

Finally, washdown experiments documented in Ref.

3.2 also revealed that potential for large pieces being

forced through when subjected to break or spray

water flow is negligible. Once again substantial

erosion might occur over time. For these pieces the

most dominant transport pathways are

1. Advection of large debris generated below the

lowest grating

2. Erosion of large debris by break flow and

subsequent transport, and

3. Advection of large pieces through

discontinuities in the floor gratings.

3 Note that flow velocity of 150 ft/s corresponds to a situation in

which blowdown flow from a main steam line break flows

through 1/8" of the drywell cross-section

'To maximize pressure drop, fine water droplets were added to

the airflow.

3-5 NUREG/CR-6369
Controlling Phenomena and Plant Features

(a) Before Exposure to Water

(b) After Exposure to Water

Figure 3-4. Erosion of large debris trapped on floor grating by water flow.

NUJREG/CR-6369 3-6
Controlling Phenomena and Plant Features

30

Test Cbndiltions'

Size: Large

25 _ .. Thickness: 1" . . . ..... . . ...... . . Flow: Break

'O 20 .. . . ... . . ..... . . . . . . . . . . .

1 E-20 ,

n15 ... ..... . . . . . ... . . . .. . .. . . . .. . . .. .

lo . . . e . .... . . .. .. . . .

5 10 . . . .. .- . . . /. . .. . . . .. .. A. . . . ..

b e ~~E-3 A

a) ,

0 20 40 60 -so 100 120 140 160 181

Erosion Time (m)

Figure 3-5. Erosion as a function of time for large pieces trapped on floor grating. (Flow is _- 50 GpM/ft2 )

0

3-7 3-7 NUREG/CR-6369
Controlling Phenomena and Plant Features

3.2.3 Large-Canvassed

The study concluded that transport of large

canvassed pieces is unlikely either by advection or

by erosion. Therefore, these pieces were classified as

"non-transportable."

3.3 References

3.2 D. V. Rao et al, "Drywell Debris Transport

Study: Experimental Work Final Report,"

NUREG / CR-6369, Supplement 1, Science

and Engineering Associates, Inc., 1997

3.3 NEDO-32686, "Utility Resolution Guidance for

ECCS Suction Strainer Blockage," Boiling

Water Reactor Owners' Group, 1996.

3.1 D. V. Rao and C. J. Shaffer, "Drywell Debris

Transport Study: Calculational Work Final

Report," NUREG / CR-6369, Supplement 2,

Science and Engineering Associates, Inc., 1997.

NUREG/CR-6369 3-8
4. Quantification of Logic Charts

Logic charts were used to integrate analytical

predictions and experimental data related to debris

generation, blowdown transport, washdown and

erosion, and drywell floor transport. A separate

logic chart was developed for each of the twenty

postulated LOCA scenarios in BWR Mark I, II and III

containments to properly account for scenariospecific variations in the thermal and hydraulic

conditions that exist in the drywell. Appendix A

presents a complete listing of all the logic charts

developed in this study. In this section, two accident

sequences are analyzed in detail to illustrate the

methodology and delineate various approaches used

to account for the effect of each physical process.

Debris transport in the drywell is a complex process

involving several coupled phenomena. Mechanistic

modeling of such a process is not practical. Where

necessary, reasonable approximations' were sought

to de-couple the problem into separate steps that

would enable the use of simple models in place of

detailed mechanistic models that would otherwise

have to be developed. Resulting first-order models

were intentionally configured to provide

conservative estimates for each step of the coupled

problem. Such conservative estimates were then

compounded to obtain the upper bound estimate for

debris transport. More realistic central estimates

were obtained by refining some of the underlying

assumptions to more accurately reflect the expected

plant conditions. Accordingly, an upper-bound and

a central estimate logic tree was developed for each

scenario. The rationale used for each approximation

in the analyses is described below. Section 2 may be

consulted for definitions of various terms used

below.

4.1 Main Steam Line Break Logic

Chart

The accident scenario analyzed here is a postulated

MSLB in a Mark I drywell. The break was assumed

to be in the mid-region of the containment where it

is likely to generate the maximum amount of debris.

In this scenario, it was assumed that the operator

would throttle the ECCS after recovering the

pressure vessel level, but before any significant water

spillage from the broken end. Also, it was assumed

that the operator would initiate the containment sprays

and would run them for thirty minutes in response to

elevated containment pressure and temperature. In the

reference plant being analyzed, the drywell vents are

offset from the floor by 18-inches resulting in a drywell

floor pool capable of holding 8000 gallons of water

before significant overflow into the vents. The drywell

has two gratings, both covering 100% of the flow crosssectional area with no significant chances for debris to

bypass the gratings. The drywell free-volume is

120,000 ft3, with 41% of it above the top grating, 37%

between the two gratings and 22% below the lower

grating. Typical drywell structures occupy the volume

above, below and between the gratings. No plant

specific features were considered. For example, this

plant has large air handling units located close to the

vent entrances, which would provide large surface area

for debris deposition, but their ability to capture debris

was ignored.

Figures 4-1 and 4-2 present the logic charts developed

to deduce upper bound and central estimates,

respectively, for the transport factor. Consistent with

postulated debris transport pathways (see Figure 2-2),

these charts de-couple the overall problem into four

sequential (but independent) processes: debris

generation, distribution after blowdown, erosion and

washdown, and transport via the drywell floor pool. A

series of analyses and experiments were undertaken to

develop necessary understanding regarding each of

these processes. The following sections describe

important findings related to each process and how

they were utilized to derive upper bound and central

estimates.

4.1.1 Debris Generation

The debris generation data provide boundary

conditions for all the subsequent processes. The

scoping analyses [Ref. 4.1] have shown that debris

transport is influenced most by the following

parameters related to debris generation: a) duration of

debris generation, b) location of debris generation, c)

medium of transport, d) debris wetness, and e) size

' Analytical models and experimental data were used to assure

that all approximations are defensible and that they provide

conservative (if not accurate) representation of the phenomena of

interest.

4-1 NUREG/CR-6369
Quantification of Logic Charts

(SeetoCA t | Debris sifiationl Disributiowdown (Section A Erosion and Washdown DrywelFlorPool Path Fraction(Section i

Advected to Vents I .Y5t§2;-Ul Vents

MARK I

UPPER BOUND

MSL BREAK

ECCS THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

Small Pieces

p0.22

Enclosu)es ---------------------- - 0.- 0E+00 Enclosures

0.00

Waterbome 3 0.000E+00 Vents ...---S---...4----- _ . 10.00

)rywell Floor

1.00 iSediment 4 0.OOOE+00 Floor

TZ5 ------------- - 1 .00

Waterborne 5 0.000E+00 Vents

10.10

ISediment 6 0.000E+00 Floor

Condensate Drainage

;0.10

3tructures-Above i

-.- iAdheres L____.00____________

0.90 7 0.000E+00 Structures-Above

.900 _-_____ ___ _

Waterbome 8 6.600E-04 Vents .

0.10

Sprays/Condensate

1.00 Sediment

StructurTes-Break 0.90

0.03 Adheres

9 5.940E-03 Floor

10 0.OOOE+00 Structures-Break

0.00 _-______ _ _

Waterbome II I .760E-03 Vents

0.10

Sprays/Condensate

1.00 Sediment

Structures-Other 0.90

A AR Adheres

12 1. 5S4E-02 Floor

13 0.000E+00 Structures-Other u uo

Structures -Break

0.25

Large-Above

0.30

Stauctures-Other

0.75

Advected to Vent

0.00

Waterborne 14 I.500E-03 Vents

1.00

Sprays/Condensate

0.02 Sediment 15 0.000E+00 Floor

_Adheres 16 7.350E-02 Structures-Break

0.98

Waterbome 17 4.500E-03 Vents

1.00

Sprays/Condensate

0.02 Sediment 18 0.000E+00 Floor

0.00

Adheres 19 2.205E-Ot Structures-Other

MSL Break

1.00

0.98 20 8.O0OE-02 Vents

I1.00 .. . . .. . 1 2 1E co ue Enclosures 21 0.000E+00 Enclosures

B o 10ge 00 - ---- ----- ----- ---- ------- -_______ --

0.08 t Waterbore

iDrywell Floor i I _-_____-____-_-__-_ --------- - _--.-- .

-------- I

22 0.000E+00 Vents

0.00 ISediment 23 | 0.000E+00 Floor

1.00

Waterbome 24 0.000E+00 Vents

,____ _ _ __ _ _ _. _ _ I _ _ _ _ _ _ __ _ _ _ _ _ _ _

20.00

11'Sediment - ----- 25 0.000E+00 Floor

Sprays/Condensate

,0.02

Structures-Break i

.0 lAdhe0es

1.00

T O ---- _ _ 26 o.OOOE+00 Structures-Break

0.98 Waterborne 27 0.000+00 Vents

; iO.00

; Sprays/Condensate i

i 10.02 tSediment

; St1.tures-Other 1.00

0.00 LAdheres

t _____. 2_ 0.OOOE+00 Floor

29 0.000E+00 Structures-Other

0.98

Canvassed 30 4.OOO-01 Structures/Floor

U MMM

note: Fractions are normalized to each debris class

Figure 4-1. Logic chart for upper bound estimate of transport factor for a MSLB scenario.

NUREG/CR-6369 4-2
Quantification of Logic Charts

LOCA Type Debris Classification| sbuo (S Erosion and Washdown Drywell Floor Pool Path Fraction(Section F

(Sectio 4.) I (Section .11 4.12 1 (Section 4.1.3) 1 (Section 4.1.4) 4oc1.5) FinNo 

Auvecteu to vents I.144E-01 Vents U

MARK I

CENTRAL ESTIMATE

MSL BREAK

ECCS THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

0.52

Enclsurcs 23 I Enclosures A~ ~ ~~7 nl2220-3Ecoue

U

0U0

Waterbome 3 0.000E+00 Vents ,_________________ _ I --- i0.00 Drywell Floor

ir 0.01 Is ediment 4 2.200E.-03 Floo ___ ___ __ ___ ___ .1 __ __ __ __ __ __ _

1.00

Waterborne 5 8.800E-07 Vents

0.01

Sediment 6 8.712E.-05 Floor

Condensate Drainage

0.01

Structures-Above

0.04 Adheres Small Pieces

)0.22

0.99

7 8.7 12E-03 Structures-Above

8 I f 0.99

Waterbome 8 .I 100E-04 Vents

0.01

Sprays/Condensate

0.50 Sediment

Structures-Break 0.99

0.10 Adheres

Vents

1.089E-02 f Floor

10 I .1 00F-02 Structures -Break I. -... 0.50

Waterbome II 3.520E-04 Vents

0.01

Sprays/Condensate

0.50 Sediment Structures-Other 0.99

0.32 Adheres

t_ 12 { 3.485E-02 Floor

I3 A 3520E-0 Stmcturec-Other

Structures-Break

0.15

Large-Above

0.34

Structures-Other

0.85

0.50

Waterbome 14 5.1 00E-04 Vents

1.00

Sprays/Condensate

0.01 Sedimeet 15 0.000E+00 Floor

Adheres 16 5.0499E-02 Structures-Break

0.99

Waterbome 17 2.890E-03 Vents

1.00

Sprays/Condensate

0.01 Sediment is 0.000E+00 Floor

_Adheres 19 2.861E-01 Structures-Other MSL Break

1.00

0.99 Advected to Vent 20 3.600E-02 Vents

0.90 2 4 ~Enclosures 21 4.OOOE-04 I Enclosures Large-Below

0.04 0 10.01

Waterborne 22 O.OOOE+00 Vents

10.00

Drywell Floor

EA. iA 0.04 Sediment 23 I .600E-03 Floor

1.00

Waterbome 24 0.0OOE+00 Vents

'0200

dmet- J 25 4.0001E-06 Floor

Sprays/Condensate

0.01

Structures-Break

0.01 Adheres

1.00

26 3.960E-04 Structures-Break

0.99

Waterborue 27 O.OOOE+00 Vents

i0.00

Sprays/Condensate

0.01 Sediment Structures-Other 1.00

0.04 Adheres

f 20 ISOOB-OS Floor

29 I .584E3-03 Structures-Other

0.99

Canvassed 30 4.000F-n I Structures/Floor 4 _ _ _ _ _ _ _ _ _ - - . :_L * - " _... A..1_ I I-. 

UL-.: rFractions are normalizea to eacn debris class

Figure 4-2. Logic chart for central estimate of transport factor for a MSLB scenario.

4-3 NUREG/CR-6369
Quantification of Logic Charts

distribution of generated debris. Debris size

classification information was explicitly used in

Figures 4-1 and 4-2 under the "debris classification"

heading. Information gathered on the other three

processes was used in the latter part of the logic tree

quantification.

4.1.1.1 Key Findings

Figure 2-3 provides an overview of various analyses

performed to develop basic understanding of debris

generation by steam jets in a BWR drywell. These

analyses included:

* RELAP calculations to estimate break flow,

including its thermodynamic state, as a

function of time,

* CFD calculations to draw insights related to

deflection of gaseous jets by typical drywell

structures located in its path,

* Review of experimental data related to debris

generation by expanding air jets, and

* Review of limited experimental data on debris

generation by steam jets.

In addition, two bench-top experiments were

conducted to draw insights related to debris wetness

following a postulated main steam line break.

NUREG/CR-6369, Supplement 2 documents some of

these calculations and their results in detail.

Important conclusions of these analyses are as

follows:

1. Debris generation occurs within seconds after LOCA.

The duration of debris generation is important

to determine the thermal and hydraulic

conditions to which the debris is subjected

during its transport. Debris generation was

known to be strongly dependent on the flow

dynamic pressure at the target pipe [Ref. 4.31.

The dynamic pressure, defined as pV2/2gC, is

dependent on the flow velocity and pressure at

the break plane (i.e., higher flow velocities and

pressure at the nozzle would translate into

higher dynamic pressure at the target). As

shown in Figure 4-3, the steam flow velocity at

the break exit plane remains nearly sonic for the

first twenty seconds, although it decreases

slightly from 900 ft/s to 800 ft/s. During the

same time, however, the fluid density decreases

rapidly due to reduction in the vessel pressure

from 1050 psi to 300 psi. As a result, the

dynamic pressure on a target located in the close

vicinity of the break falls rapidly with time,

decreasing to a third of its initial value within the

first five seconds. Because, debris generation is

directly proportional to the jet dynamic pressure

[Ref. 4.2], it can be concluded that majority of the

debris would be generated within the first five

seconds. For the sake of simplicity, it is reasonable

to assume that debris generation occurs

instantaneously after a LOCA2 .

2. Debris generation is limited to a zone of influence

surrounding the break. Further destruction or

degradation of the debris outside the zone of influence is

negligible. This approximation is vital to de-couple

the problem that would enable modeling debris

transport independent of debris generation.

Analytical efforts were undertaken to study jet

expansion in the zone of influence, when subjected

to structural congestion typical of the drywell midregion. These studies found that the same

processes that generate debris from the target pipes

would also deflect and diffuse the jet within the

zone of influence. Therefore, at the exit of the zone

of influence' the flow velocities would be in the

range of 50-100 ft/s. Flow velocities in the

remainder of the drywell are in the range of 30-45

ft/s, with the exception of the neck region where

flow velocities as high as 100 ft/s are possible.

Experiments were conducted to study if gas

velocities as high as 150 ft/s can cause any damage

to debris [Ref. 4.3, Section 2, Tests 41 through 44].

These tests have shown that no damage would be

expected in the region outside the zone of

influence.

3. Steam is the medium of transport. Medium of

transport affects pathways available for transport.

For example, debris entrained by steam would be

distributed through out the drywell. On the other

hand, water-borne debris would be carried

downward to the drywell floor without interaction

with a majority of drywell structures. Calculations

were undertaken to determine the constituents of

the break flow and draw conclusions related to the

medium of transport. As shown in Figure 4-3,

these calculations suggest that a primarily dry

2 Sensitivity analyses suggest that transport factors are weakly

dependent on this assumption. It was found to result in a slightly

conservative estimate of debris transport factor.

'If such an approximation is invalid, then more complex modeling

effort integrating debris generation and transport would be

necessary.

'The zone of influence tends to be hemispherical for a postulated

single-ended MSLB in a congested region.

NUREG/CR-6369 4-4
Quantification of Logic Charts

t

I M ........................ ........

x .... -... , ".. , , , , , " -. - - - - -- -

-1-1',-;;Y",-,-""",-,O", 0.8

0 0.6

U

U. 2

IL

0.4

0.2

0

a

lb

Nomenclature

M Mass Flow Rate (Ibis)

P Vessel Pressure (psi)

o a Void Fraction

x quality

Mo Mass Flow rate @ 0 s

Po Pressure at 0 s

* I . , , . I , i I

in MSIV Closure

I ., ,I [ I I I

0 10 20 30 40 50

Time After LOCA (s)

900

800

c

Ccc

.i 700

tz

mCa

6.

c600

0

500 3 

400

300

Velocity (ft/s)

/ omenclature\

/ V Steam Velocity at Break Plane (ftIs)

Pd Dynamic Pressure in the Jet (psi)

Pdo Dynamic Pressure in the jet @ 0 s

" - -Ratio of Dynamic Pressure

- - \_

1

0.8

0.6 C.

a.

0

0.4

0.2

0

I

- I % %

a I I I I I I I I I I I I I I 

0 10 20 30 40 50

Time after LOCA (s)

Figure 4-3. Blowdown data corresponding to a postulated main steam line break in a BWR/4 plant.

NUREG/CR-6369 4-5
steam jet expands into the containment with an

equilibrium quality at the stagnation point

greater than 0.8 over the first twenty seconds.

The corresponding equilibrium void fraction is

0.99. Therefore, it is very likely that debris are

entrained and transported through the drywell

by steam continuum, with suspended water

droplet field.

4. The debris would be nearly dry. Wet debris tends

to be heavier (i.e., higher inertia) and will be

more likely to impact the structural

impediments in their path and adhere to them.

Two bench-top experiments were conducted as

part of this study (Ref. 4.4) to establish likely

debris wetness following a MSLB. In the first

one, the fiberglass insulation fragments of

different size were held stationary and were

continually exposed to up to 2 minutes of steam

flowing across it. In the second test, a small-scale

steam jet from an industrial boiler was used to

fragment the aged insulation blanket. In both

cases, debris weight was measured while they

were wet and after they were completely dried.

A maximum increase in weight of 20% was

noted in these tests with all the condensed water

film on the outer surface; the bulk of the

fragment volume was essentially dry. Such a

slight increase is unlikely to effect transport or

capture. Therefore, it is reasonable to assume

that debris would be dry. Note that this

assumption minimizes the potential for debris

capture in the drywell.

5. Debris size distribution is uncertain. Typical sizes

of the debris as they exit the zone of influence

and the mass of debris belonging to each size

group are vital components necessary to

estimate overall transport factor. Existing data

suggest that generated debris can be generally

characterized as small, large and largecanvassed. Past experiments have provided

some data that can be used to derive debris size

distribution typical of main steam line breaks

(see Section 5). However, any such effort would

be associated with large uncertainties. No

attempts were made as part of this study to

develop applicable debris size distribution.

4.1.1.2 Upper Bound Estimates

Sizes of the debris as they exit the zone of influence

are a crucial input necessary to determine applicable

transport pathways. Existing experimental data

suggest that fibrous insulation debris can be broadly

classified into three size groups, small, large and

large-canvassed. Also, experiments conducted as part

of this study established that gratings are effective at

capturing all the large debris transported to them by

steam or water flow. Hence, it is likely that large

debris generated above the lowest grating would

follow substantially different pathways compared to

those generated below. To accommodate these

differences, the large debris were further divided

into two groups: large-above and large-below. The

focus of this study was to obtain transport factors for

each of these debris sizes (i.e., small, large-above,

large-below, and large canvassed). To meet this

objective, a value of 1.0 was assigned for,, T2, T13 1

and T4 in Figure 4-1. Such a choice automatically

normalizes values under the heading "Fractions" to

each size class (i.e., all fractions belonging to each

size class add up to 1.0). Section 5 describes how the

actual size distribution data, if available for the

particular scenario of interest, can be used to

calculate the overall transport factor (Fzo').

4.1.1.3 Central Estimates

Same approach as above.

4.1.2 Distribution at the End of Blowdown

The objective of this step was to estimate where the

debris would be located at the end of blowdown.

The allowable final locations are vents (suppression

pool), enclosures, structures-above, structures-break,

structures-other and drywellfloor. As the initial (or

boundary) condition, it was assumed that dry debris

exits the zone of influence, and that, due to high

flow velocities, debris deposition is negligible within

the zone of influence. Finally, it was assumed that

all of the debris is entrained and transported by

steam flow. During transport outside the zone of

influence the debris would not undergo further

destruction or reattachment.

Subject to these conditions, the fraction of debris

advected to vents during blowdown can be

expressed as:

bdi -Xen- Xsa -Xsb -X -Xidf

Where, Fbd is the blowdown transport factor for ith

size debris, and XVent X'sa, X'sb, X'sof and Xidf are

NUREG/CR-6369 4-6
Quantification of Logic Charts

capture fractions associated with enclosures,

structures-above, structures-break, structures-other, and

drywellfloor, respectively. Each of these individual

fractions are the product of the fraction of debris

carried into that region by gas flow and the

efficiency of the structures in that region to capture

it size debris. Analyses and experiments were

conducted to draw insights related to both these

phenomena.

4.1.2.1 Key Findings

An analytical approach was adopted to estimate the

quantity of debris being carried into each region of

the containment. For this purpose, CFD simulation

of the drywell was undertaken to determine likely

bulk flow patterns that would exist in the drywell

following a LOCA. These CFD calculations utilized

break flow estimates from RELAP simulations as a

boundary condition. To minimize computational

effort, the actual drywell structures were not

modeled. Instead, porous media with a pressure

drop approximated structural impediments to flow.

The resulting bulk flow patterns were utilized to

draw conclusions related to debris movement.

In addition, experiments were conducted to study

capture efficiencies associated with drywell

structures assembled to prototypical congestion

levels. Experimental data were obtained for a wide

range of conditions determined to be representative

of drywell thermal and hydraulic conditions

corresponding to different accident scenarios. These

experiments clearly established that structural

wetness plays a vital role in deposition. Hence,

further analytical efforts were devoted to draw

insights related to the build-up of water film on

drywell structures. Based on all these analyses, the

following conclusions were drawn related to debris

transport outside the zone of influence:

1. Debris becomes intermixed with the containment

atmosphere. Immediately after LOCA (t =0 s),

vent flow is minimal due to large frictional

losses at the vent entrance and presence of

water in the down-comers 5 . During this time

(< 1.0 second after LOCA), the break flow is

primarily used to pressurize the containment.

CFD simulations suggest that strong

recirculating flow patterns exist in the

drywell during this short interval, leading to

nearly uniform concentration of debris

within the drywell. This finding was used to

set the initial conditions for transport (i.e.,

uniform concentration of small debris in the

drywell at t=O s).

2. Vents clear shortly after LOCA. Debris

advection to suppression pool commences

once the vents clear. Several MELCOR6

analyses were conducted to estimate time

taken for vent clearance in Mark I and Mark

II containments (see Figure 4-4) [Ref. 4.6].

For the smallest of the operating BWR

drywells (free-volume = 125,000 ft3), vents

were predicted to be cleared in 0.5 seconds

after assuming that no condensation occurs

in the drywell (either on structures or due to

isentropic jet expansion). For an average size

drywell (140,000 ft3) coupled with more

realistic estimates of steam condensation,

vents were cleared at 0.8 seconds. After

vents cleared, the drywell was maintained at

a quasi-steady pressure of 45 psia for about

30 seconds. As shown in Figure 4-4, during

this quasi-steady state, the flow rate closely

follows the breakflow shown in Figure 4-3.

3. Moderateflow velocities and relatively simpler

bulkflow patterns drive debris transport outside

the zone of influence. Figure 4-5 illustrates

typical bulk flow patterns expected in the

drywell following MSLB [Ref. 4.5]. This

corresponds to the case in which direction of

the break flow is horizontal and the vents are

cleared at 0 seconds. Several such runs with

different break orientations were used to

draw insights related to likely flow patterns

that would exist in the drywell following a

LOCA. These calculations suggest that flow

velocities in the majority of the drywell

would be in the range of 25-45 ft/s, with the

exception of the neck region where they may

as high as 100 ft/s. The bulk flow patterns

would cause continuous mixing of the debris

with drywell atmosphere. It is likely that at

any given time mass of debris advected to

vents can be approximated by a simple

volume turnover model.

4. Debris advection by blowdownflow occurs on a

short time scale. Analyses have shown that the

5 In Mark I and II drywells, down-comers would be occupied by

water slug 4-6 ft in height.

6 MELCOR was used because it already has a detailed vent

model.

NUREG/CR-6369 4-7
tt

r&

Y..

D

9

CI

ni

0

3~

Y0

0q

IDt

rt

Y.

0

0

0

P1)

Ol USL-4 Dogwneonw Flow Vioaottlo

325

300

275

250

s 225

j 200

175

150

125

100

45

40

35 Y

30 1

25

230

225

200

175

I 125

75

50

25

0

- -41_- Side O

.... .. Il1,o -.-

400

200

0

*800

- 600

20

Is3 . .

0 5 10 15 20 25 30

To& (a)

0 5 10 tS 20 25 30

TME (a)

ISL-4 Tmp ,rakoro (a) 460

440

420

... .....W....

..

-- _a-- tv, Sad

- 41- etwel - Aimw

... _a... Wt@ SEt

__-SQWr_ Pool

R 400 ... '_ .... t_ ... . .. tAlortIIII

380

360

7.8

7.7

7 . 7

7 . S

7.6

7.2

7. t

IWISL-4 Drwel Pool Lev8ts

-- ,-- gd" I

-0- book udrr

-.- U.- Odt 2

- U-cavity

Ovarfew 

............................................................................

.1

0 5 10 t15 20 25 30

TMt (a)

340

320

300

O' , - - I I

1 I

§ b----------__--,,-___

i________ O- - - - -_____. ---- _--- a . .......-.. . . ....

0 5 to 15 20 25 30

TWS (a)
Quantification of Logic Charts

fluid temperature and vectors

(- 5 v 9E+02)

26.0

z

*

m

e

t

e

r

s

*

-8 .5

600

558

515

473

430

388

345

-11. 0

x *Moeters*

1

1

-I

1. 0

Figure 4-5. CFD code predictions for quasi-steady flow patterns that

exist in the drywell following a MSLB.

4-9 NUREG/CR-6369
rate at which debris is advected from the drywell is

a product of the concentration in the drywell and the

volumetric flow rate. For fully mixed flow

conditions, assuming debris generation at 0 seconds

and no removal from the flow, the fraction of

generated debris that would be advected during t

seconds can be calculated from the mass

conservation equation as:

F(t ) = (M, O-M (t ))/M -_ I - e ( 'c-t)/1

(4-1)

where,

F(t) = fraction of initial inventory

transported in t seconds.

MO = = debris mass inventory in the

drywell at t=0,

M = debris mass inventory in the

drywell at t,

Tvent = time required to clear

vents/downcomers (0.5 -1.0 s

for Mark I)

= turnover time7 (3.4, 4.2 and 5.4

seconds, for Mark I, II and III)

potential for debris removal by this

mechanism. In a turbulent flow (such as that

expected in the drywell), the flow turbulence

can reduce likelihood of debris falling out due

to gravitational settling. It has long been

known that gravitational settling is negligible

if the root-mean-square turbulent velocity is

higher than the terminal velocity of the

suspended particle. The CFD calculations

were undertaken to estimate turbulent kinetic

energy (which is a measure of the RMS

velocity) in different regions of the drywell as

a function of time. These calculations

suggested that turbulent kinetic energy in the

bulk of the containment atmosphere following

a MSLB is greater than 24 joules/kg.

Corresponding turbulence root-mean-square

velocity is approximately 21 ft/s, which is far

in excess of the debris fragments terminal

velocity of 2-5 ft/s. Therefore, it can be

concluded that containment flow dynamics

and turbulence levels would be sufficient to

keep debris in suspension. This conclusion is

further validated by separate effects tests (Ref.

4.3, Section 2.4.1). Also note that neglecting

gravitational settling results in higher

transport.

For a Mark I drywell (Tvent = 0.75 s and X =

3.4 s), the transport factor is 0.40, 0.71, 0.93

and 0.98 corresponding to t=2.5, 5, 10, and 15

seconds, respectively. Therefore, the debris

that remains in suspension would be advected

to the vents by blowdown flow within the first

15 seconds. During these first 15 seconds, the

containment conditions remain quasi-steady.

Hence, it is not necessary to undertake a

transient debris transport analysis. This

conclusion was used to simplify transport

models significantly.

Potentialfor gravitational settling of debris is

negligible. Gravitational settling is one

mechanism by which debris can be removed

from the flow. For quiescent flow, debris

terminal velocity' is a good indicator of the

'Turn over time is defined as the ratio of "mass of drywell

atmosphere at 45 psia corresponding to quasi-steady condition

(lb.)" to "break flow rate (Ib./s)".

'Terminal velocity is a measure of particle inertia and is equal to

its gravitational settling velocity in quiescent air (or water).

Usually a particle will remain in suspension if its terminal

velocity is much lower than the flow root-mean-square velocity.

5. A fraction of the generated debris would be

captured by structures. Experiments

conducted at similar operating conditions

clearly demonstrated that small and large

debris would be captured on gratings and

other drywell structures. The fraction

captured was found to be a strong function of

the structural wetness, and types of

structures located in each region.

7. Structural wetness varies with time.

Experiments and analyses have shown that

small and large debris possess enough

inertia to impact the structures as they are

carried across them by bulk gas movement.

If the structures are dry, however, the debris

will not adhere to them. On the other hand,

wet structures can be effective at removing

debris from the flow stream. Therefore,

considerable analytical effort was

undertaken to study various means by

which drywell structures would become

wet. Condensation of steam on relatively

cool drywell structures and water droplet

NUREG/CR-6369 4-10
Quantification of Logic Charts

deposition9 on drywell structures were

identified as two mechanisms that would

wet outer surfaces of the structures.

MELCOR calculations were used to estimate

water film buildup on the structures due to

steam condensation alone. As shown in

Figure 4-6, condensation occurs rather

quickly with water film building up to 75

pm within the first second. Also, it would

take approximately

2 seconds for the liquid film thickness to

reach a saturated state'. Liquid film buildup

would likely be faster than shown in Figure

4-5 due to water droplet deposition, which

was not considered in the MELCOR

analyses. This information was used during

the design of experiments described in Ref.

4.2. In these experiments, the capture data

was obtained for all three possible surface

conditions: dry, wet (- 75-pm water film)

and saturated (= 150-[tm water film).

4.1.2.2 Upper Bound Estimates

3. All structures would be dryfor the first two seconds.

This assumption is very conservative

considering that MELCOR calculations

suggested that the film thickness on majority of

structures due to steam condensation alone

would be as high as 75 pm within the first

second (see Figure 4-6). Even higher thicknesses

are likely if film buildup due to water droplet

deposition is considered.

4. No capture of small debris during the first 2 seconds.

Tests have shown that dry pipes and I-beams

would not capture small debris. On the other

hand, the dry gratings would have capture

efficiency of approximately 6% [Ref. 2.4]. To be

conservative, however, it was assumed that no

deposition occurs on any structures during the

first 2 seconds.

5. Approximately 35% of the small debris would be

advected to the vents within thefirst two seconds.

Subject to above assumptions, the fraction of

small debris advected to vents can be estimated

as

P -= 1 - exp(-(2-Te,,)/It) (4.2)

As evident from the discussions above, several

uncertainties exist in the predictions related to vital

thermal-hydraulic phenomena, including vent

clearance time and structural wetness. The upper

bound transport factors were obtained by assuming

"worst-case" T/H response.

Transport of Small Debris

Figure 4-7 illustrates the logic used to predict

distribution of small debris in the drywell at the end

of blowdown. It is based on the following

assumptions:

1. Debris is generated instantaneously after the LOCA

(t=0 sec)

2. Vents are cleared of water and quasi-steady venting

starts at 0.5 s after LOCA (T,,,, = 0.5 s). The most

likely time for vent clearing would be closer to

0.8 s. On the other hand, it would not be lower

than 0.5 s, which represents the worst case.

Using T..., = 0.5 s and T = 3.4 s, F'2 is estimated

to be 0.35, which is the value used in Figure 4-7

for the fraction of debris transported in the first

two seconds. The remaining 65% of the debris

would be uniformly distributed in the drywell at

the 2-second mark.

6. Debris contained in the upper region at the end of 2

seconds will pass through two gratings, while the

debris contained in the middle region goes through

one grating. The debris contained in the lower

region does not go through any gratings. This

picture of transport is consistent with the bulk

flow patterns expected in the drywell following

a MSLB (see Figure 4-5).

7. Ratios of the drywell volume contained above the

highest grating (upper region), between the two

gratings (middle region) and below the lowest

grating (lower region) are 0.41, 0.37 and 0.22,

respectively. These values were obtained by

proportioning the drywell inventory according

to the volume of each region.

'Water droplets are introduced into the containment when the

steam jet over expands (shocks) in the containment. The wave

stability calculations suggest that these droplets will likely be in

the range of 10-20 pgm in diameter.

' Saturation condition corresponds to a situation in which

addition of water by condensation is off-set by film drainage by

gravitational and entrainment mechanisms.

8. Debris would be captured at the floor gratings with

an efficiency of 15%. Capture of debris on

structures other than gratings is negligible

(including vents). Figure 4-8 illustrates the

measured capture efficiency of the floor gratings

4-11 NUREG/CR-6369
2 5 0

2 2 5

2 0 0

I I I

Film Thickness on Vertical Surfaces

Main Steam Line Break

Break Side of Drywell

U)

0

ci,

Cn

9,_ Ile

0

E

U1 75

1 50

1 25

1 00

7 5

- Upper Neck

- - - At Break in Neck

- A- Upper Level

.... ... Mid Level

- -_*-- Near Floor

_ _E I _

_ I-U-

'9-I

AU

.l ',-A

A

.0 - - -

/ rr

.*---- .1

/ . *1 . .

/~A .

-IIII / A

/I /

/ / /

5 0

2 5

o/

/

El'

/

0 '-4

0 .0

~ - A-I-,--- l l l l

0 . 4 0 . 8 1 . 2 1 . 6 2 . 0

Time After Break (seconds)

Figure 4-6. Liquid film build-up on drywell structures due to steam condensation.

NUREG/CR-6369 4-12
Quantification of Logic Charts

commonly employed in BWR drywells. Measured

capture efficiency for wet gratings varied between

15-35%, with a mean value of 25%. In the present

calculation, a capture efficiency of 15% was

assumed. The remaining 85% would be transported

downwards. These split fractions (0.15 and 0.85)

were used to quantify each subsequent branch in

Figure 4-7.

As shown in Figure 4-7, the upper bound identifies

four pathways for transport of small debris to the

vents during blowdown:

1. Advection of 35% of the small debris generated

during first two seconds when the drywell

structures are dry,

2. Advection of 100% of the debris contained in

the lower region of the drywell at the end of 2

seconds,

3. Advection of 85% of the debris contained in

the middle region at the end of 2 seconds, and

4. Advection of 72.25% of the debris contained in

the upper region of the drywell after

accounting for capture at both gratings.

Together these pathways resulted in transport of

89% of the small debris to the vents during

blowdown. The remainder (11%) was deposited on

the floor gratings located below the spray heads.

Assuming uniform flow conditions, a quarter of this

captured debris was assumed to be on the grating

located directly underneath the break (structuresbreak) and the remaining 75% is assumed to have

been on the rest of the grating (structures-other).

Thus a value of 0.03 and 0.08 were used for XVSb and

X, in Figure 4-1. The remaining factors (X V,,, XL,

and Vd were assigned 0.

Transport of Large Debris

Advection of 100% of the large-below debris to the

vents was assumed. This assumption is supported

by CEESI tests in which large debris pieces (1.5 ft. x

1.5 ft.) were transported horizontally up to 50 feet.

Factors Xien, X'sa, X1 sb, Xiso, and Xidf were assigned

a value of zero signifying no capture of large-below

debris in the drywell.

It is assumed that all the large-above debris would be

captured on the gratings. Implicitly, it was assumed

that floor grating covers the entire flow cross-section

without allowing any chance for bypass. A quarter

of this captured debris was assumed to be on the

grating located directly underneath the break

(structures-break) and the remaining 75% is assumed to

have been on the rest of the grating (structures-other).

Thus a value of 0.75 and 0.25 were used for Xiso and

Xisb in Figure 4-1. The remaining factors (X'en , Xisa,

and X'df) were assigned 0.

4.1.2.3 Central Estimates

The central estimates were based on assumptions that

were judged to be more representative (or realistic) of

debris transport in the drywell. As

discussed below, even the central estimates possess a

certain margin of conservatism.

Transport of Small Debris

The rationale used for deriving the central estimate of

debris distribution at the end of blowdown is

illustrated in Figure 4-9. The fundamental differences

between central estimate and upper bound estimate are

as follows:

1. Vents clear of water at 0.75 s after LOCA. The

sensitivity analyses suggested that 0.75 seconds

is more representative of the Mark I and II

Drywells.

2. Before the vents clear, 10% of the small debris would

be captured on the two gratings together. These

values were obtained by combining the CFD

calculation results with the experimental data.

The CFD runs suggested that a debris particle

generated at the break location and carried by

steam flow without slip would pass through at

least two gratings within the first 0.75 seconds.

For conditions typical of this 0.75 seconds (low

structural wetness and high velocities), a single

grating capture fraction of 6-9% was measured

in the separate effects tests (Ref. 4.3, Section 2,

Test 26). For two successive gratings estimated

capture efficiency is 12 to 18%. However, a

value of 10% was used in this study, which is

conservative.

3. Drywell structures contained in upper, middle and

lower regions (other than the gratings) will remove

10% of the debris passing through them. The

structural assemblies in the upper, middle and

lower regions were found to have combined

surface area for deposition larger than the

structures used in the CEESI facility for which a

capture efficiency of 10% was measured (see

Figure 4-10). Note that structures used in the

CEESI testing were selected based on a survey of

4-13 NUREG/CR-6369
Initiating Event Surface Wetting Distribution in Interaction with Interaction with Interaction with Path Fraction To Vent Location of Debris

Drywell Upper Grating Lower Grating Vent Structures

and Floor

Incomplete I 3.5000E-01 X Transported Into Vent

0.35 1 Downcomers

I BWR MAR Goes by 2 1.9255E-01 X Transported Into Vent

UPPER BOUND ESTIMATE Goes by 1.00 Downcomers

0.85 ICaptured 0.QOQOEQO Deposited onto Floor Near Vents

Small Pieces Upper Regn Captured 3.3979E-02 Structures Below Spray Heads

1.00 0.41 0.15

Captured 5 3.9975E-02 Structures Below Spray Heads

0.15

Goes By 6 2.0443E-01 X Transported Into Vent

Complete Goes By 10 Downcmers

0.65 Middle Region 0.85 Captured7 0 .0000E00

0.37 Captured 8 3.6075E-02

Goes by 9 1.4300E-01 X Trasported Into Vent

Lower Region |1.00 Downcomer

Captured 10 0.OOOOEOO Deposited onto Floor Near Vents

Figure 4-7. Secondary logic tree used to evaluate upper bound debris distribution after blowdown.

NUREG/CR-6369 4-14
Quantification of Logic Charts

1 00

9 0

80

70

I I I, I I I I

GRATING

* CEESI(4 in) - Wet

o CEESI(4 in) - Dry/Partial Wet

* CEESI(3 in) - Wet

* ARL - Wet

& ARL - Dry

I.-1

0-

0

C-)

M..

C,

6 0

5 0

40

30

. .... .. Capture Efficiency

Capture Efficiency

Used in Central Estimate

Used in Upper Bound Estimate

20

1 0

0

!....25%

. . . . .. .. . . 3.. ..... .. i ........ 2..5,%. . .. . . A! 15%

- J I a I I I I I II

0 2 4 6

Debris Loading (Ibm/100 ft2)

8 1 0

Figure 4-8. Efficiency for capture of small debris by floor grating.

4-15 NUREG/CR-6369
Debris Size Distribution Distribution in Interaction Interation Interaction Interaction Interaction I nteraction Path Fraction To Vent Location of Debris

Classification at Time of Drywell with with Upper with with Lower with with Vent

Vent Structures in Grating Structures in Grating Structures in Structures

Clearance Upper Middle Lower and Floor

Region Region Region

Structures (Above) 1 2.0000E-02 Structures Above Spray

0.02 Heads

Structures (Below) 2 8.0000E-02 Structures Below Spray

0.08 Heads

Enclosures 3 1.OOOOE-02 Enclosures

0.01

Goes By 4 1.4814E-01 X Transported Into Vent

Goes By __.99 Downcomers

BWR MAR 0.90 Captured 5 1.4963E-03 Deposited onto Floor Near Goes CNR ESTIM E G s BVents

Goes By | Captured 1.6626E-02 Structures Below Spray

CENTRL 90 E 010 6Heads

Captred .541E-02Structures Below Spray

Small Pieces 0.75 0.25Heads

1.00 Goes By Captured 8 2.4631 E-02 Structures Below Spray

0.90 0.10 Heads

Captured 9 8.2103E-02 Structures Below Spray

Upper Region 0.25 Heads

0.41 Captured (Above) 10 1.8245E-02 Structures Above Spray

0.05 Heads

Captured (Below) 11 1.8245E-02 Structures Below Spray

0.05 Heads

Goes B 12 1.9805E-01 X Transported Into Vent

Goes By _Ao.99 Downcomers

0.0 Capt red 13 2.0005E-03 Deposited onto Floor Near

0.01 Vents

10.75 Captured 2.2228E-02 Structures Below Spray

0.89 1.90 1 4 Heads

Middle Region 150Captured 7.4092E-02 Structures Below Spray

0.37 0.25 1Heads

Captured 16 3.2930E-02 Structures Below Spray

0.10 Heads

Goes By 17 1.7446E-01 X Transported Into Vent

Goes By _0.99 Downcomers

Lower Region 0.90 Captured 18 1.7622E-03 Deposited onto Floor Near

Le R n 0.01 Vents

.2 Captured 19 1.9580E-02 Structures Below Spray

010 Heads

Page 1- 1

Figure 4-9. Secondary logic tree used to obtain the central estimate for debris distribution after blowdown.

NUREG/CR-6369 414-16
Quantification of Logic Charts

1 00

9 0

8 0

7 0

I I . I I I I I

0~

C--)

U,

-D

I-BEAMS AND PIPES

ARL Capture Data

Projected Area of

Projected Area of

* CEESI(4 in) - Wet

o CEESI(4 in) - Dry/Partial Wet -

* CEESI(3 in) - Wet

A ARL - I-Beams

Mean for CEESI Wet Tests.-------- 

6 0

5 0

4 o

3 0

Adapted to CEESI Geometry

I-Beams Was 50% of Total Area.

Pipes Was 20% of Total Area.

2 0

1 0

0

I I

0 2 4 6 8 1 0

Debris Loading (Ibm/100 ft2)

Figure 4-10. Structure capture traction.

structures that exist in various regions of the BWR

drywell. Also, the debris residence in the structural

region of CEESI is much smaller than that expected

in the BWR drywell. Thus direct use of CEESI data

is reasonable, although it may underestimate

capture. Each grating removes an additional 25% of the

debris passing through them. As shown in Figure 4-8

above, central estimate for grating capture efficiency

is 25%.

4. Vents capture 1% of the debris. In the CEESI

tests, Mark I vents were found to be

ineffective at capturing small debris,

irrespective of structural and debris wetness.

5. Enclosures trap 1% of the debris. It is likely that

a fraction of the debris would enter the

enclosures (e.g., reactor cavity) where they

would become trapped. Based on engineering

judgment this fraction was assumed to be

0.01.

Subject to above assumptions, it is estimated that

approximately 52% of the small debris would be

transported to the vents. The remaining debris

would be distributed in the drywell as follows: 1%

on enclosures (Xl,), 1% on drywellfloor or vents (XVd),

4% on structures-above (XIV), 10% on structures-break

(XsSb) and 32% on structures-other (XOJ.

Transport of Large Debris

Advection of 90% of the large-below debris is assumed.

The remaining 10% would be trapped in the enclosures

or on drywell structures such as support cables." A

nominal 1% was assumed to enter the enclosures and

the remaining 9% on structures or drywell floor. These

estimates were judged to be conservative, but

necessitated by the lack of experimental data

Central estimates are also based on the assumption that

100% of the large-above debris would be captured on

the gratings. However, it is assumed that only 15%

would be trapped on the grating directly below the

break. This division is based on the insight gained by

CEESI integrated effects tests where the majority of

large pieces were blown away from the break area by

the flow velocity. Therefore,

" Experiments have shown that support cables and small diameter

pipes normal to the flow provide ideal locations for large debris to

wrap around.

4-17 NUREG/CR-6369
a higher fraction is expected to be on the grating

away from the break as compared to below the

break.

4.1.3 Erosion and Washdown

This step addresses potential for re-entrainment of

small debris and erosion of large debris by

containment sprays. As shown in Figure 2-2, debris

deposited on structure-break and structures-other

would be subject to water flow which may erode

and/or wash them down to the drywell floor. Reentrainment refers to the process by which small

pieces of insulation debris loosely attached to the

drywell structures would be entrained and carried

by cascading water flow. Erosion refers to the

process by which water would erode primarily large

insulation pieces trapped on structures (thus not

available for entrainment). This step relies on the

outcome of the previous step to determine the

quantity and the type of debris that would be

located on each structure. The ECCS flow rates and

the drywell layout information were coupled to

calculate the water flow impinging on each

structure. Experiments were conducted to evaluate

potential for washdown and erosion of debris

corresponding to these conditions.

4.1.3.1 Key Findings

For the accident scenario of present interest, break

overflow is not expected, as it was assumed that the

operator would throttle the flow upon recovering

vessel level. Debris deposited on structures-break and

structures-other would be subjected to containment

spray flow of 4500 GPM distributed across the

drywell cross-section for thirty minutes.

Corresponding to those flow conditions, washdown

data were obtained for small and large debris

[Ref. 4.3]. The data suggest that the containment

sprays will washdown the majority of the small

debris located on structures subjected to spray flow.

The experiments also established that the spray

water would not result in significant erosion of large

pieces.

Small debris deposited on structures-above would be

subjected to condensate drainage. No experimental

data were obtained for such cases. Instead

engineering judgment was used to estimate

washdown by condensate drainage.

4.1.3.2 Upper Bound

The upper bound estimate was obtained based on the

following assumptions:

1. In thirty minutes, the containment sprays would

wash down 100% of the small debris deposited on

structures. At the end of blowdown,

approximately 11% of the small debris are

retained on the floor gratings, which would be

exposed to containment spray flow for thirty

minutes. Experimental data obtained for similar

conditions suggest that sprays would washdown

100% of the debris deposited on pipes and 40-

50% debris deposited on gratings. Nevertheless,

a washdown factor of 1.0 was used for structuresother and structures-break in Figure 4-1.

2. The containment sprays would washdown 2% of the

large debris. Experimental data suggest that

sprays would erode a maximum of 2% of the

large debris. A washdown factor of 0.02 was

used for large-above captured on structures-other

and structures-break in Figure 4-1.

3. The condensate drainage will transport 10% of small

debris 2. CEESI experience suggests that very

little (if any) debris would be transported by

condensate drainage. Directly applicable

experimental data is non-existent. To be

conservative, a small debris washdown fraction

of 0.10 was assigned to structures-above.

Thus the upper bound was based on a value of 1.0 for

YsO and Yssb, and 0.1 for Yssa. Also, a value of 0.02 was

used for Y

1 so and Ylsb4.1.3.3 Central Estimate

Central estimates were obtained based on the following

assumptions:

1. In thirty minutes, the containment sprays would

wash down 50% of the small debris deposited on

structures by inertial deposition. Experimental data

suggest that sprays would washdown 100% of

the debris deposited on pipes and 40-50% debris

deposited on gratings. However, not all the

debris would be subjected to sprays. Both the

Barsebdck-2 event and the CEESI experiments

demonstrate that large structures located above

can prevent washdown of debris deposited on

12 In this particular case no debris were deposited on the structureabove as shown in Figure 4-1 and explained in Section 4.1.2.2.

NUREG/CR-6369 4-18
Quantification of Logic Charts

smaller structures underneath, and also debris

deposited on drywell walls will not likely be

washed down. A washdown transport factor

of 0.5 was used for small debris deposited on

structures-break and structures-other.

2. The containment sprays would washdown 1% of

the large debris. Experimental data suggest

that, sprays would washdown a maximum of

2% of the large debris. A more realistic

washdown transport factor of 0.01 was used

for large debris deposited on structures-break

and structures-other.

3. The condensate drainage will transport 1% of

small debris. This estimate is based on

engineering judgment and was applied for

small debris deposited on structures-above.

The central estimate was derived using a value of 0.5

for Ysso and Ysb, and 0.01 for Yssa. In addition, a

value of 0.01 was used for Yls 0 and Ylsb.

4.1.4 Drywell Floor Pool Transport

The quantity of debris reaching the drywell floor as

a result of blowdown and washdown are given by

FFlOOr Xsa Y + X'b Ysb + X'O YSO + Xdf

(2.5)

The objective of this final step is to evaluate what

fraction of this quantity will be transported to the

vents when subjected to flow dynamics established

by containment spray flow.

The analyses have shown that deep water pools

formed on the Mark I drywell floor due to

containment spray water accumulation would allow

the debris particles to settle down (Ref. 4.4). The

objective of this step is to estimate what fraction of

debris would be transported to the vents versus

what fraction would settle down. Detailed CFD

simulations of the water flow on the drywell floor

were coupled with experimental data [Ref. 4.6] to

draw necessary insights.

8000 gallons. The vents are offset from the floor by

approximately 18 inches. The sprays were assumed to

add water to the entire cross-section of the drywell

floor. Computational fluid dynamics calculations were

undertaken to predict flow patterns and turbulence

levels that exist in the drywell pool as a result of

containment sprays (see Figures 4-11 and 4-12). Several

sensitivity analyses were conducted to study the

impact of plant-specific variations in various

parameters, such as ECCS flow rate, presence of

structures and vent-pipe offset height (i.e., height of the

vent pipes compared to drywell floor). These

sensitivity analyses demonstrated that during

containment spray operation, low flow velocities (<

0.05 ft/s) and low turbulence levels (turbulence kinetic

energy"3 < 10 ft2/s2) characterize the bulk of the Mark I

drywell pool. The flow dynamics may be slightly more

turbulent over a small region closer to the vent

entrance. Past experiments have shown that small and

large debris would settle down under such flow

conditions [Ref. 4.6]. Also the flow would not resuspend debris deposited previously on the drywell

floor. Therefore, for this scenario it is very likely that a

major fraction of the debris would settle down.

4.1.4.2 Upper Bound

Upper bound was obtained subject to the following

assumptions:

1. Small debris deposited in the bulk of the drywell

would settle down (or sediment). The flow patterns

were determined to be quiescent and thus would

allow for debris sedimentation.

2. Small debris deposited in a small region close to the

vent entrance will be transported. As shown in

Figure 4-11 and 4-12, turbulence levels are

slightly higher in the close proximity of the

vents. Small debris' 4 brought into this region by

spray water flow would likely enter the vents

before they settle down. Under this

approximation, about 10% of the debris brought

down by the sprays were estimated to enter the

vents. Hence, a value of 0.1 was used for pool

transport factor (ZE) in Figure 4-1.

4.1.4.1 Key Findings

Drywell pool forms as a result of accumulation of

containment spray flow on the drywell floor before

it fills up and starts to overflow into the vents. For

the Mark I containment being modeled, the

containment spray flow rate is approximately 4500

GPM and the drywell pool capacity is approximately

13 Turbulence kinetic energy is an indicator of residual pool

turbulence and is expressed as 1⁄2 U'_,, where U_ is the root-meansquare velocity of the flow.

" Small debris has a settling velocity of 0.05 ft/s and would take 40

seconds to settle down in an 18-inch deep pool. During the same

time, debris would travel 18-inches or more horizontally. Thus

debris deposited in a circular region 18-inches in radius extending

from the vent entrance may be transported into the vents.

4-19 NUREG/CR-6369
i

r

,

I

r¶it; - o -~ 
rs-tare "Cr-fl.. Sr e Ct r tc
Table 4-1. Upper bound estimate of debris transport reactions for a MSLB scenario.

DEBRIS TRANSPORT RESULTS

Plant Design: ______I

Estimate: UPPER BO FIB INSULATION

Break: _

ECCS: ECCS THRO

Sprays: _ SPRAYS OP

TREE QUANTIFICATION

_ trct= e Structures Structures Transport

Debris Classification Vents Enclosures floor Srte S res Str Transpor

Small Pieces 9.01OE-01 O.OOOE+00 9.900F-02 O.OOOE+00 0.OOOE+00 O.OOOE+00 0.9010

Large Pieces -Above 2.OOOE-02 0 0.OOOE+00 0 2.450E-01 7.350E-0l 0.0200

Large Pieces-Below I.OOOE+00 0.OOOE+00 0.000E+00 0 0.OOOE+00 0.OOOE+00 1.0000

*1 i i I t i

FINAL DISTRIBUIHONS (Horizontal)

Debris Classification

. .

Vents Enclosures Floor tructures

Abov

:ructures

Break

MrucLUtUS

Other

Small Pieces 90.10% 0.00% 9.90% 0.00% I 0.00% 0.00%

Large Pieces-Above 2.00% 0% 0.00% I 0% 24.50% 73.50%

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00% I 0.00%

I i it t

___ - _

Debris Transport Fractions

1.250

1.000

' 0.750 0

E 0.500 LA

I All large, all debris and all zone

of influence are described in

- Section 5. 0.250 -_

n nnn U.UUU ASrrll Debris Large Above Large Below All Large Debris All Debris All Zone-ofGratings Gratings Influence

NUREG/CR-6369 4-22
Quantification of Logic Charts

3. Eroded component of the large pieces will be

transported to vents by spray flow. Experiments

have shown that secondary debris from

erosion of large debris tended to be individual

fibers (or small clumps) that would be

maintained in suspension at very low

velocities. A pool transport factor of 1.0 was

used for erosions brought down by the

containment spray flow.

4. Large and small pieces previously deposited on the

drywellfloor will not be re-entrained.

Experimental data have confirmed this

assumption for drywell floor pool flows

typical of those established by containment

sprays. (Note that some of the large pieces

that are dry may become suspended for a

short duration while air is trapped in the

insulation, but the potential transport was

estimated to be minimal for this scenario.)

4.1.4.3 Central Estimate

In the central estimate, a more rigorous approach

was used to estimate the potential for small debris

settling in a region closer to the vent entrance. In

particular, CFD calculations were carried out to

examine the movement of debris deposited in the

pool at different locations. These calculations

suggest that nearly all the debris would settle down

irrespective of the location of its introduction. This

finding was used to lower transport factor for small

debris (ZS) from 0.1 to 0.01. The other two

assumptions regarding erosion and re-entrainment

were retained.

4.1.5 Results of Quantification

The branch-split factors used for each step are

shown in Figure 4-1 and 4-2. Successive numbers

were multiplied to obtain the fractions of debris

transported by each pathway. These fractions are

shown under heading "Fractions" in Figures 4-1 and

4-2. Fractions associated with those pathways that

ended with vents being the "Final Location" were

added together to calculate the transport factor for

each class of debris Fs, FIB, and Fib. Tables 4-1 and 4-2

provide the estimated transport factors as functions

of debris size.

4.1.5.1 Upper Bound

Two dominant pathways were identified for debris

transport during blowdown:

1. Advection of small debris by steam, and

2. Advection of large debris generated below the

lowest grating (i.e., large-below) by steam.

As shown in Table 4-1, together they contributed

towards transport of 90% of small and 100% of largebelow debris during blowdown. In Figure 4-1, both

these two pathways were highlighted as a measure of

their importance.

Four additional transport pathways contribute towards

transport during washdown. These pathways pertain

to washdown and subsequent transport of small and

large-above debris deposited on structures-break and

structures-other by containment sprays. As shown in

Figure 4-1, their contribution is minimal.

4.1.5.2 Central Estimate

Dominant pathways identified in the central estimate

are same as those identified above, i.e.,

1. Advection of small debris by steam, and

2. Advection of large-below debris by steam.

However, as shown in Table 4-2, their contribution is

considerably smaller compared to the upper bound.

Only 52% of small debris are transported to the vents

with all of it occurring during blowdown.

4.2 Recirculation Line Break

The accident scenario considered is a postulated

recirculation line break (RLB) in the mid-region of a

Mark I drywell. It is assumed that the operator would

throttle the ECCS one-hour after the accident. Until

that point, the ECCS make-up flow of 25, 000 GPM was

assumed to spill through the break into the drywell.

The spillage accumulates on the drywell floor, until the

water level exceeds 18-inches at which point water

overflows into the vents. The drywell is assumed to

have same geometrical characteristics analyzed in

Section 4.1. Figures 4-13 and 4-14 are the logic charts

developed to estimate upper bound and central

estimate of the transport factor.

4-23 NUREG/CR-6369
Table 4-2. Central estimate of debris transport fractions for a MSLB scenario

DEBRIS TRANSPORT RESULTS

Plant Design: lRI

Estimnate: CETA ES INS AO

Break: _ E BREA

ECCS: ECCS HO LE

Sprays: SPRAYS OPERATE1)

TREE QUANTIFICATION

Debris Classification Vents Enclosures Floor Structures Structures Structures Transport

Abo~t Break Other Fraction

Srnall Pieces 5.221E-OI 1.000E-02 2.183E-01 3.960E-02 5.OOOE-02 1.600E-01 0.5221

Large Pieces-Above 1.OOOE-02 0 O.OOOE+00 0 1.485E1-01 8.415E-01 0.0100

Large Pieces-Below 9.OOE-0 1.000E-02 4.050E-02 0 9.900E3-03 3.960E-02 0.9000

I 4- 4 4 4 4 4

FINAL rizont.

Debris Classification Vents Enclos ures Floor Above Break Other

Simll Pieces 52.21% 1.00% 21.83% 3.96% 5.00% 16.00%

Large Pieces-Above I 1.00% I 0% 0.00% I 0% 14.85% 84.15%

Large Pieces-Below 90.00% 1.00% 4.05% 1 00/. 0.99% 3.96%

4 4- 4 4 I 4-

I - S - - I - ml -

D_ ebris Tranpor F. rat.o

Debris Transport Fractions

1.000

0.750 - _- ____

1 :P.500.

lL.

n^.^

All large, all debris and all

zone of influence are

U vU - ll|1 - described in Section 5.

0.000

Sriall Debris Large Above Large Below All Large Debris All Debris All Zone-ofGratings Gratings Inf luence

NUREG/CR-6369 4-24
Quantification of Logic Charts

LOCA Type (Section1 Debris Classification DItiuinAtrErosion andWabon DrelFlrPol at Faton(cin

4.t1 (Section 4.11 IBlowdown (S~ection (section 4.13)I (~S* i 4.14) No. 4.1.5) FnlLcto

1 4.1.2) I I Advected to Vents I 0.000E+00 Vents

MARK I

UPPER BOUND

RL BREAK

ECCS THROTTLED

NO SPRAYS

FIBROUS INSULATION

Small Pieces

10.22

_0.00 -----------------------------------------------------

'Enclosures -- -2 0.00E-+00 Encl-osures .I A- ..._ - -- --- __ _ _ _ _ _

'0.00

i Watt

i 1.00

Drywell Floor

trbome 3 2.200E-01 Vents

I- r 4

1.00 Sediment 4 0.OOO+00 Floor

0.00

Waterborne 5 0.OOOE+00 Vents

iSediment 6 0.000E+00 Floor L ---------------- __

Condensate Drainage

io. lo

Structures-Above i

* -Adheres .... ... ] 

0.00

7 0.0001E+00 Structures-Above

0.90

Waterborne 8 0.OOOE+00 Vents

1.0 j0 --

Recirculation Flow i

1.00 - - Sdime0t

Structures-Break i 0.00Z

0.00 :Adheres

t9 0.00E+00 Floor ..._ _ _ __ _ _ I_ __ _ _ _ _ 1- _ _ _ _

10 0.000E+00 Structures-Break

0.00

Waterbome II 0.000E+00 Vents

r--z----- j 1.00

i Condensate Drainage i

10.10 -- Sediment

:Structures-Other i 0.00

0 u00 Adheres

t 12 j 0.000E+00 Floor ______________

13 0.OOOE+00 Structures-Other

Structures-Break

1.00

Large-Above

0.30

iStructures-Other

0.00

Advected to Vent

Waterbome 14 3.600E-02 Vents

1.00

Recirculation Flow 5 __Floor

0.12 Sediment 15 0.OOOE+00 Floor

Adheres 16 | 2.640E-01 Structures-Break

0.88 1 _

Waterbome 17 0.000E+00 Vents

rF j-----------__ 1 I.00I

Condensate Drainage i

i°oo ISediment 18 0.000E+00 Floor

__ 0.0 z _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ I __ _ _ _ _ _ _ 'Adheres 19 0.OOOE+00 Structures-Other

RL Break

1.00

1.00

20 8.00OE-02 Vents

1.00 _2___________________________.

Enclosures 21 0.000E-I00 Enclosures

Large-Below 00

008t Waterborne 22 0.000E+00 Vents

'5.00

Drywell Floor

i0.00 ibecument 23 0.000E+00 Floor l ...------- - 4- 0.00

Waterbomne 24 0 .OOOE+00 Vents

LSediment 0.000E+00 E2 Floor

Recirculation Flow

'1____00-___________

Structures-Break

0 00 -. lAdheres

0.00

26 0.OOOE+00 Structures-Break

. 00 ----------------------- ____ ____ _ _ I

Waterbonne 27 0.000E+00 Vents

1.00 ___

II I .00

Condensate Drainage I

i i'0.00 '--,!Sediment

:Structures-Other _ 0!0 --0 -

0.00 ' Adheres

____________ I I

_____________ 28 i 0.000E+00 i Floor

29 0.000E+00 Structures-Other

------- I . r

-- ______________.--- --- -- --- - I

1.00 30 4.OOOE-01 Structures/Floor Canvassed

nan . - . I

note: Fractions are normalized to each debris class

Figure 4-13. Logic chart for upper bound estimate of transport factor for a RLB scenario.

4-25 NUREG/CR-6369
Quantification of Logic Charts

LOAIye DersC I,,,,~~ BoDisr town (S teto IErosion and Washdown I Drywell Floor Pool Path IFraction (Section FnlLcto (Section 4.) (Section 4.11 BlwIw S(Section 4.1.3) (Section 4.1.4) No 4.1.5) FnlLcto

~ I _ - _ _ _ 

Mdvecu to v ems I I.012E-01 Vents

MARK I

CENTRAL ESTIMATE

RL BREAK

ECCS THROTTLED

NO SPRAYS

FIBROUS INSULATION

Small Pieces

10.22

0.46 .

Enclosures 2 j2 2.200E-03 Enclosures

J.01

Waterbome 3 4.400E-02 Vents

I- F F

Drywell Floor I' 00

. OA A

).20 iSediment 4 0.000E+00 Floor

Waterbore 5 4.400E-05 Vents

FSediment .. .0.000E+00 6 Floor

Condensate Drainage

0.01

Structures-Above

0.02 Adheres

0.00

7 4.356E-03 Structures-Above

F I- 0.99

Waterbome 8 I.760E-02 Vents

Recirculation Flow

1.00

Structures-Break

0.08 Adheres

S 1.00

.___ __ Floor

0.00

10 0.OOOE+00 Structures-Break --n .^n +----- U.UU

Waterbome 5.060E-04 Vents

Condensate Drainage

0.01

Structures-Other

0.23 Adheres

_1.00

Sediment 12 0.000E+00 Floor

0.00

13 5.009E-02 Structures-Other

Structures-Break

0.15

Large-Above

0.34

Structures-Other

0.85

Advected to Vent

0.99 1 Waterborne 14 4.080E-03 Vents

1.00

Recirculation Flow

0.08 iSediment _ 15 0.OOOE+00 Floor

0.00

Adheres 16 4.692E-02 Structures-Break

0.92

Waterbome 17 0.000E+00 Vents

Condensate Drainage i

(0.00 0.lSed00cnt 0.000E+00 18 Floor

IAdheres 19 2.890E-01 Structures-Other RL Break

1.00

1.00

20 3.600E-02 Vents

0.90 21 _ _ Enclosur

Enclosures. 21 4.000E-04 Enclosures |LargeBelow

0.04

0.01I

Waterbome 22 I .440E-03 Vents

0.90

Drywell Floor

l l l

0.04 1Sediment 23 I .600E-04 Floor

0.10

Waterbome 24 2.000E-04 Vents

1.00 I

iSediment 25 0.OOOE3+00 I Floor_______

Recirculation Flow

0.50

Structures-Break

0.01 Adheres

0.00

26 2.000E-04 Structures-Break

0.50u

Waterborne 27 0.000E+00 Vents

Condensate Drainage

10.00

Structures-Other i

0.04 Adheres

r-F ---------------- --I ISediment 28 | 0.OOOE+00 Floor ---- __---_____-______

0.00

29 I .600E-03 Structures-Other .1- L __________ ___________

].00

Canvassed 30 4.00OE-01 qtnuctrures.-/Ftr A

0.40 - - 6

note: Fractions are normalized to each debris class

Figure 4-14. Logic chart for central estimate of transport factor for a RLB scenario.

NUREG/CR-6369 4-26
Quantification of Logic Charts

Similar to the previous case, the overall transport

problem is decomposed into four independent

processes: debris generation, distribution at the end

of blowdown, washdown and erosion and drywell

pool transport. The fundamental differences

between this and the previous MSLB scenario are:

1. Debris generation occurs due to two-phase

blowdown, instead of steam as in the case of

main steam line break,

2. A portion of the debris would be transported

by the water component of the blowdown

flow,

3. Break overflow introduces a large quantity of

water which has the potential to erode large

pieces of insulation located on floor gratings,

and

4. The drywell pool would likely to be more

turbulent.

Several analyses were conducted to quantify the

impact of these differences on debris transport.

Figures 2-3 and 2-4 summarized the analyses

undertaken in this study.

4.2.1 Debris Classification

As in the previous case, data is gathered regarding

the following parameters related to debris

generation: a) duration of debris generation, b)

location of debris generation, c) debris wetness, d)

medium of transport, and e) size distribution of

debris.

4.2.1.1 Key Findings

Debris generation by the recirculation break is

expected to be different from the MSLB by the fact

that blowdown initially consists of water, followed

by two-phase mixtures in the later stage of accident

progression. Insights relating to jet expansion and

potential for debris generation were drawn from the

following investigations:

1. CSQ simulation of two-phase jet expansion

from various stagnation conditions (pressure

and sub-cooling) and loads impinged by such

an expansion [Ref. 4.7], and

2. Experimental study of two-phase jet

expansion [Ref. 4.8].

These analyses were augmented by a series of hand

calculations, as necessary, to apply their results to

the present study. Important conclusions of these

analyses are as follows:

1. Debris generation occurs over a prolonged period

after LOCA. Calculations suggest that mainly

water at a flow rate of approximately 25000 lb/s

exits the nozzle initially (stagnation static

quality < 0.02 and void-fraction < 50% for the

first 5 seconds) (See Figure 4-15). The

corresponding nozzle flow velocity is on the

order of 30-100 ft/s. As shown in Figure 4-16,

the liquid effluent forms an approximately

spherically shape within the piping region as a

result of flashing and jet deflection [Ref. 4.5 and

4.81. Also it decelerates significantly within a

short region due to structural drag. Typically

such jets are expected to destroy debris

contained in a spherical region no larger than 3

to 5 nozzle-diameters in radius [Ref. 4.9].

Debris generated during this phase will likely

be entrained and transported by water

component as it cascades down to the drywell

floor.

Later on substantial flashing occurs within the

broken pipe, resulting in increased flow quality

at the nozzle. After about 20 seconds, as shown

in Figure 4-15, the break flow consists of a steam

continuum (void fraction > 0.90) with

suspended liquid water droplets (quality >

35%). Steam flow at velocities up to 800 ft/s

penetrates the piping region. Due to low

structural drag, high velocities are maintained

over a region extending up to 10 nozzlediameters [Ref. 4.2 and 4.5]. Debris generated

during this phase will likely be entrained by

steam and transported through the drywell in a

manner similar to that for the main steam line

break.

2. Afraction of the debris (480%) would be transported

by steam, with the remaining (=20%) transported by

water. As a result of a recirculation line break,

debris could be generated in a spherical region

extending up to 10 nozzle-diameters in radius

[Ref. 4.21. However, as described above,

insulation contained in the close proximity of

the break (< 5 nozzle-diameters) will be

generated within the first five seconds and will

be transported by water. The remainder will be

generated later into accident (t> 20 s) and will

be transported by steam continuum.

4-27 NUREG/CR-6369
Quantification of Logic Charts

1

0.8

0.6

0

.2

IU. 0.4

0.2

0

0

1800

1600

1400

i 1200

*D 1000 U

0

> 800

i 600

400

200

0

~~ ~..................----

Nomenclature

M Mass flow rate (Ibis) P Vessel Pressure (psi)

a Void Fraction

".'\x Quality

Mo 26,000 IbIs

Po 1020 psi

* ** x

r,.-,, ,11.~ , .. 1,,,,1,,111.

p I I I I II I I

I

I

I

I

i

I

5 10 15 20 25 30 35 40 45 50

Time After LOCA (s)

3

2.5 0

0

2 I

fa

1.5 M

._

a0.5

0 0 5 10 15 20 25 30 35 40 45 500

Time After LOCA (s)

Figure 4-15. Blowdown data corresponding to a postulated recirculation line break in a BWR/4.

NUREG/CR-6369 4-28
-%-q0 =a 04c

= 0

re

I0

- - -

--

-e

-tp i

-S.

~E nsko m
3. Several plant layouts were used to estimate

the relative fractions of debris transported by

water versus steam. Based on these analyses,

it is concluded that no larger than 20% of the

total generated debris would be transported

by water, with the remaining 80% being

transported by steam. These fractions were

used to derive the central estimates for the

transport factor. On the other hand, the

upper bound transport factor was derived

assuming that 100% of the debris would be

entrained by water.

4. The debris and the structures would be wet

(nearly saturated). As shown in Figure 4-15,

the water component of the blowdown flow

is as high as 5000 lb/s even during the later

stages of the accident (water component =

M(1-x)). Therefore, it is very likely that all

structures and debris would be wet.

5. Debris size distribution is uncertain. There are

no existing data on types of debris generated

by recirculation line breaks. It is assumed

that the debris can be broadly divided into

the same three groups, small, large and largecanvassed.

4.2.1.2 Upper Bound

The debris was divided into four groups depending

on their size and location of generation. They are

small, large-above, large-below and large-canvassed.

Once again, a value of 1.0 was used for TA, T2,3 , and

114 . The focus of the study is to estimate transport

factors for each debris size.

4.2.1.3 Central Estimate

Same as Section 4.2.1.2.

4.2.2 Distribution at the End of Blowdown

This step addresses transport of small and large

pieces by water and steam components. As the

boundary condition, it is assumed that small, large

and large-canvassed pieces exit the zone of

influence, and will not degrade any further during

their transport outside the zone of influence. The

debris would be wet and would be generated over a

longer period. The objective of this step was to

estimate where the debris would be located at the

end of blowdown.

4.2.2.1 Key Findings

The key findings related to debris transport during

recirculation line break are:

1. Small debris entrained by water will be deposited in

the drywell pool instantaneously. As previously

noted, break flow consists mainly of water

during the first 5 seconds. Assuming that water

spreads uniformly over a quarter of the drywell

cross-section, the average flow rates exceed 200

GPM/ft 2 . Experiments have shown that such

high water flow will entrain and transport all

the small debris. Hence, it is likely that all small

debris initially entrained by water would

cascade with the break flow down to the

drywell pool.

2. Advection by water medium would also occur over a

short time scale with nearly 100% of debris

transported. Calculations suggest that break

liquid effluent would form a pool on the floor

and could flow into the vents within 4 to 5

seconds. For most Mark I drywells, one to two

pool turnovers are expected during blowdown.

Assuming two turnovers, it can be easily shown

that approximately 85% of the debris would be

advected to the vents during blowdown. This

transport would be augmented by the ECCS

recirculation flow of 25, 000 GPM, which would

be added to the pool after blowdown. During

this time it is likely that the pool would be

highly turbulent due to phenomena such as

sloshing, flashing and flow dynamics.

Therefore, it is unlikely that any debris,

irrespective of its size, would settle in the pool.

3. Advection by steam resembles transport by MSLB.

The bulk flow patterns in the drywell volume

during later stages of RLB blowdown were

predicted by approximating the break flow to

be single-phase steam". These analyses suggest

that steam bulk flow patterns in the

containment are similar to the previous

predictions for main steam line break, although

they are less severe. Approximating them by

steam flow patterns resulting from a MSLB is

conservative.

This assumption ignores the interfacial momentum transfer

between steam and water. Therefore, it is likely to result in higher

steam velocities, which maximizes the potential for transport.

NUREG/CR-6369 4-30
Quantification of Logic Charts

4.2.2.2 Upper Bound Estimates

The model assumes that 100% of the small debris

would be entrained by the liquid medium and be

transported to the drywell floor instantaneously.

Depending on the drywell pool capacity and break

flow, all or a fraction of the debris would be

transported to the vents during blowdown itself. In

this analysis it was assumed that 100% of the small

debris are located in the drywell pool at the end of

blowdown. This assumption has no impact on the

overall outcome since break overflow results in

transport of nearly 100% of this debris.

It is estimated that 100% of the large debris

produced above the lowest grating will be trapped

directly beneath the break on the floor grating. This

estimate is a direct result of the assumption that all

debris would be entrained and transported by water

as it cascades down.

Finally, all of the large-debris generated below the

lowest grating will be transported into the drywell

pool by water.

4.2.2.3 Central Estimates

Figure 4-17 illustrates the logic used to estimate the

capture fractions for small debris. The rationale

used for quantification of important steps is as

follows:

1. Approximately 20% of the small debris would be

entrained and transported by water to the drywell

floor. Additional 1% of the debris may be captured

in the enclosures. Experiments have shown

that all of the small debris entrained by water

would be carried to the drywell structures. A

small quantity of debris may enter enclosures

such as the reactor cavity where they will be

captured either during steam-borne advection

or during water-borne advection. A value of

1% was used to represent this fraction trapped

in the enclosures.

2. Remaining 79% of the small debris would be

transported similarly to a MSLB described in

Section 4.1.2.2. The important steps are as

follows:

a) The debris becomes inter-mixed with

the drywell volume, with 41% of it

above the upper grating, 37% between

two gratings and 22% below the lowest

grating.

b) The debris contained above the upper

grating would be deposited on 1)

structures in the upper region, 2) upper

grating, 3) structures in the mid-region, 4)

lower grating, 5) structures in the lower

region and 6) vents. Structures will

remove debris with an efficiency of 10%,

where as the gratings have an efficiency of

25%.

c) The debris contained between the two

gratings would be deposited on

1) structures in the mid-region, 2) lower

grating, 3) structures in the lower region

and 4) vents.

d) The debris contained below the lower

grating would be deposited on 1)

structures in the lower region and 2)

vents.

3. For large debris generated below the lowest

grating (large-below), same distribution as main

steam line break was used: 90% advected to

vents, 1% in enclosures, 4% deposited at the vent

entrances, and 5% captured on structures such as

support cables. Of the 5% captured on

structures, it is assumes that 25% would be

located directly beneath the break and the

remaining 75% distributed over the rest of the

drywell.

4. All large-above, debris would be captured on the

lower grating. It is assumed that 25% of that

debris would be on structures-break, where as

75% would be on structures-other.

4.2.3 Erosion and Washdown

In this scenario, water is introduced into the

containment as a result of break overflow for a period

of one-hour, at a rate of 25, 000 GPM. As it cascades

down the drywell structures, water spreads over a

cross-section as large as one-fourth of the drywell

cross-section. Corresponding water flow is nearly 50

GPM/fte at the lower grating. Debris deposited

underneath the break, but in the break quadrant, will

be subjected these high water flows. Experiments were

conducted to study the impact of these large quantities

of water on fibrous insulation transport. The findings

of these experiments are summarized below.

4-31 NUREG/CR-6369
Oa

crTp

a3.

U.)

&

Cy\

ITJ

clQ

0

0

r.

0

t

0A

&-

r,

To

aQMo

rKD

rn

~r

1h

el)

0

0

C)

Debris Size Initial Distribution in Interaction Interatin naton Interaction Interaction Interaction

Classification Distribution Drywell with with Upper with with Lower with wih Vent

Structures in Grating Structures in Grating Structures in Structures

Upper Middle Lower and Floor

Region Region Region

Enclosures

Path Fraction To Vent Location of Debris

___I __I__ +.

0.01

YeVaterborne

D.20

2

3

4

1.OOOOE-02

2.0000E-01

I.3149E-01

1 .3282E-03

Enclosures

Drywell Floor

Small Pieces

1.00

EI~

Airborne

0.79

Goes By

G oes By Captured

uRat 1L | lg D7ured

Goes .. By 0

lMAtin Ge s B0Capturedu0.2

0.90 0.10

Captured

Upper Region 0.25

0.41 Captured (Above)

x

-TF 4758E-02

6 4.9192E-02 Structures Below Spray

Heads

Structures Below Spray

Heads

7.2 1863E-02

8

Transported Into Vent

Downcomers

Deposited onto Floor Near

Vents

Structures Below Spray

Heads

0.05

8

10

11

7.2878E-02

1.6195E-02

Structures Below Spray

Heads

Structures Above Spray

Heads

Structures Below Spray

0.05tu D~bW Heads

1.6195E-02

1 .7580E-01 0.05 Goes By

Goes By 0o.99

Goes By o0go Captured

0.75 Cpue Goes By

Goe B Ca tured 0.10

0.2

x Transported Into Vent

Deoie Downcomers ont Flor. ea

1 .777E-. Vents

1.7757E-03 12

13

14

I .9730E-027

6.5768E-02

Deposited onto Floor Near

Vents

Structures Below Spray

Heads

Structures Below Spray

Heads

Structures Below Spray

_ Heads

KMiddIl Ppnion VIIKIUIG I \ylUl, 1 C.nnti ird~ 0.25

15 2.9230E-02

0.1

0.10 16 x Downcomers

Lower Region 1

0.22

Goes By

Goes By lo 99 ogo0 Captured

0.01

Captured

ni0

1.5486E-01 X Transported Into Vent

Downcomers 16

17

17

183

1 RA~qrE-nA

_ 1 .7380E-02

Deposited onto Floor Near

Vents

Structures Below Spray

. _ J _ Heads_ _ _
Quantification of Logic Charts

4.2.3.1 Key Findings

1. All small debris located in the quadrant in which

break is located will be re-entrained and washed

down to the drywellfloor. Experiments

conducted as part of the present study [Ref.

4.31 clearly established that recirculating

ECCS flow will washdown small debris

deposited previously on pipes, I-beams or

gratings.

2. Large debris will not beforced through the

gratings. They would be eroded gradually at a

constant rate. Experiments were conducted to

specifically address if large debris would be

forced through gratings when subjected

water flows typical of recirculating ECCS

flow. In these experiments, pieces as thin as

1/8 inch were exposed to water flow of

approximately 50 GPM/ft2 . The pieces were

not forced through the grating

instantaneously (or on a short-time scale).

Instead they were eroded over a longer time

scale (see Figures 3-3 and 3-5).

3. Erosions resemble small clumps of individual

fibers. Once again experimental data were

used to draw this conclusion.

4.2.3.2 Upper Bound

For this scenario all small debris were transported to

the drywell floor during blowdown. Therefore,

structural washdown of small debris is not

important.

Erosion of large-above debris captured on gratings

during blowdown is the only mechanism considered

in the upper bound. Based on experimental data

shown in Figure 3-5, it is estimated that about 12% of

that debris would be eroded when subjected to one

hour of ECCS flow. Note that 12% value assumed is

an upper bound for the erosion measured in the

experiments (including experimental uncertainties).

The washdown may be lower if the operator

throttles ECCS flow well before one hour.

previously deposited on structures-break would be

transported to the drywell pool as a result of

washdown. Other drywell structures would not be

subject to water flow other than condensate drainage.

A transport fraction of 0.01 was assigned to quantify

small quantities of debris that may be transported by

condensate drainage.

Erosion of large-above debris deposited on structuresbreak was estimated to be 8% based on the experimental

data, assuming that insulation would be subjected to 1-

hr of ECCS recirculation flow of 25,000 GPM.

The water flow may break loose a fraction of the largebelow debris trapped by structures below the lowest

grating. No experimental data was available to

quantify this effect. It was assumed that 50% of such

debris are knocked down by the flow and brought to

the drywell pool.

4.2.4 Drywell Floor Pool

A drywell pool forms as a result of accumulation of

break overflow on the drywell floor before it fills up

and spills into the vents. For a small BWR/4 reactor

with Mark I containment, the unthrottled break

overflow rate is approximately 25000 GPM and the

drywell pool capacity is approximately 8000 gallons.

The vents are offset from the floor by approximately 18

inches. It is assumed that structures located between

the break and the drywell would distribute the flow

over a quarter of the drywell cross-section. CFD

calculations were undertaken to predict flow patterns

and turbulence levels that exist in the drywell pool as a

result of break overflow (see Figures 4-18 and 4-19).

Several sensitivity analyses were conducted to study

the impact of plant-specific variations in various

parameters, such as ECCS flow rate, presence of

structures and vent-pipe offset height (i.e., height of the

vent pipes compared to drywell floor). These

sensitivity analyses demonstrated that during

unthrottled ECCS operation, high flow velocities (< 0.5-

1 ft/s) and high turbulence levels characterize the bulk

of the drywell pool. Past experiments have shown that

at these flow conditions small and large debris would

be maintained in suspension [Ref. 4.61.

4.2.3.3 Central Estimate 4.2.4.1 Upper Bound

Experiments have shown that 100% of the small

debris deposited on structures and gratings will be

washed down by break flow across them. As a

result, it was assumed that all small debris

It was assumed that both small and large debris would

be maintained in suspension and transported to the

vents. No sedimentation is likely.

4-33 N3NUREG /CR-6369
Onant a o Kno Ojgin Coat

i,

,1

e

Ii

3uql 0-3t 3%- , JERRY X400-,F

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I 

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f : :' fl | 

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:: tA 

\: ;:y'd ff

a: S:00:03 

: 

:

:000: 

: DSt 

: l EDl:

:0: iS te:itiS: 

r\U 49-

: t: - 

:iX \:iS:) ;:f f

dofi 0S

:: -;:;kX ;fff : CaS 

l 1;S' St e \rD'LSrV0'duD7 'SS !X70 :fU704fffEV \ TySS C::00 :0 :; C0; C0

we ]:9_ d;aC f
4.3 References

4.2.4.2 Central Estimate

The central estimate also assumed that 100% of the

small debris deposited previously in the drywell

pool or brought to the pool by break overflow would

be transported during the ECCS recirculation phase.

However, it assumed that only 90% of the large

debris would be transported. The remaining 10%

would settle down in the wake regions of the

drywell structures.

4.2.5 Results of Quantification

Tables 4-3 and 4-4 present estimated transport

factors as functions of debris size.

4.2.5.1 Upper Bound

Two pathways dominate transport by recirculation

line break:

1. Water-bome advection of small debris.

2. Water-borne advection of large-below

debris.

The other significant pathway for transport is

erosion of large-above pieces and subsequent

transport by break overflow. Together these

pathways contribute towards transport of all small

and large-below debris, and approximately 12% of

the large-above debris.

4.2.5.2 Central Estimate

The dominant pathways for transport are:

1. Air-borne advection of small debris,

2. Water-bome advection of small debris,

3. Air-borne advection of large-below debris,

and

4. Washdown and subsequent transport of

small debris by break overflow.

Together these pathways resulted in transport of

75% of small debris and90% of the large-below

debris. Only 2% of the large-above debris were

transported.

4.1 D. V. Rao, et al., "Drywell Debris Transport

Study," Draft Phase 1 Letter Report, SEA 96-

3105-010-A;2, September 27, 1996.

4.2 Boiling Water Reactor Owners' Group, "Utility

Resolution Guidance for ECCS Suction Strainer

Blockage," NEDO-32686, 1996

4.3 D. V. Rao, et al., "Drywell Debris Transport

Study: Experimental Work, "NUREG/CR-6369,

Supplement 1, Science and Engineering

Associates, Inc., SEA 97-3105-A:15, September

1997.

4.4 D. V. Rao, et al., "Drywell Debris Transport

Study: Analytical Work, "NUREG/CR-6369,

Supplement 2, Science and Engineering

Associates, Inc., SEA 97-3105-A:16, September

1997.

4.5 K. Williams, "Simulation of a BWR Drywell

Flow in Response to a Recirculation -Line

LOCA using a Computational Fluid Dynamics

(CFD) Code," FSS Report: RX-96-05, Flow

Simulation Services, Inc., 1996.

4.6 P. Murthy and M. Padmanabhan, "ECCS

Strainer Model Study: Transport and

Experimental Studies in a Laboratory Flume,"

Report 31-94/M216F, Alden Research

Laboratory, Inc. 1994.

4.7 G. G. Weigand, et al., "Two-Phase Jet Loads,"

NUREG/cR-2913, Sandia National Laboratories,

SAND 82-1935, January 1983.

4.8 Electric Power Research Institute, "Two-Phase

Jet Modeling and Data Comparison," EPRI NP4362, S. Levy Incorporated, March 1986.

4.9 W. W. Durgin and J. Noreika, "the Susceptibility

of Fibrous Insulation Pillows to Debris

Formation Under Exposure to Energetic Jet

Flow," NUREG/CR-3170, Alden Research

Laboratory, Inc., 1983.

NUREG/CR-6369 4-36
Quantification of Logic Charts

Table 4-3. Upper bound estimate of debris transport fractions for a RLB scenario.

DEBRIS TRANSPORT RESULTS

PlantDesign: MARK I

Estimate: UPPER BOUND US INSULATION

Break: RL BREAK

ECCS: THROTTLED

Sprays: NO SPRAYS

TREE QUANTIFICATION

Debris Classification Vents Enclosures Floor Structures Structures Structures Transport

Above Break Other Fraction

Small Pieces 1.OOOE+00 0.OOOE+0O 0.OOOE+00 O.OOOE+00 0.OOOE+00 0.OOOE+00 1.0000

Large Pieces-Above 1.200E-01 0 0.OOOE+00 0 8.800E-01 0.000E+00 0.1200

Large Pieces-Below 1.000E+00I .OOOE+00 0.000E+00 0 O .000E+00 0.000E+00 1.0000

FINAL DISTRIBUTTONS, (Horizontal)

Struture S tructures Structures Debris Classification Vents Enclosures Floor _ Above Break Other

Small Pieces 100.00% 0.00% 0.00% 0.00% 0.00% 0.

Large Pieces-Above 12.00% 0% 0.00% 0% 88.00% 0.

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00% 0.00%

Debris Transport Fractions

1.250

1.000

0.750 Ik'

L' 0.500

0.250

Small Debris Large Above Large Below All Large Debris All Debris All Zone-ofGratings Gratings Influence

4-37 4-37 NUREG/CR-6369
Table 4-4. Central estimate of debris transport fractions for a RLB scenario.

DEBRIS TRANSPORT RESULTS

PlantDesign: MARKI

Estimate: CENTRAL ESTIMATEFIBROUS INSULATION

Break: RL BREAK

ECCS: ECCS THROTTLED

S prays: NO S PRAYS

TREE QUANTIFICATION

Debris Classification Vents Enclosures Floor Structures Structures Structures Transport Above Break Other Fraction

Small Pieces 7.425E-01 I.OOOE-02 0.000E+00 1.980E-02 0.OOOE+00 2.277E-01 0.7425

Large Pieces-Above 1.200E-02 0 0.OOOE+00 0 1.380E-01 8.500E-01 0.0120

Large Pieces-Below 9.410E-01 I1.000E-02 4.000E1-03 O 5.000E-03 4.000E-02 0.9410

FINAL DIISTIRUTIOINS (Horizontal)

Debris Classification Vents Enclosures Floor Structures Structures Structures

Above Break Other

Small Pieces 74.25% 1.00% 0.00% 1.98% 0.000/o 22.77%

Large Pieces-Above 1.20% 0% 0.00% 0% 13.80%

Large Pieces-Below 94.10% 1.00% 0.40% 0% 0.50% 0

Debris Transport Fractions

1.000

0.750-

Is 0.500-

LI.

0.250

0.000

Srnall Debris Large Above Large Below All Large Debris All Debris All Zone-ofGrabings Gratings hfluence

NUREG/CR-6369 4-38
5. Application Of The Study Results

The ultimate objective of this study was to provide a

tractable method by which an analyst could estimate

the total quantity of fibrous debris reaching the

suppression pool, or for NRC to judge applicability

of licensee calculation of debris transport. The logic

charts presented in Section 4 provide only part of the

information necessary to meet this objective. Other

information required to accomplish this objective

includes debris size distribution and differences

between the plant geometry assumed to develop the

logic charts and the actual plant features. This

section provides an approach by which logic charts

can be coupled with this additional information to

estimate quantity of debris transported to the

suppression pool.

5.1 Integration of Debris

Generation Data

The logic charts provided in Section 4 can be used to

estimate fractions of each debris size that would be

transported to the suppression pool due to

combined effects of blowdown and washdown

transport. In order to estimate the total quantity of

debris transported to the suppression pool, these

fractions have to be weighted with the size

distribution data as shown below:

Qpool= (111 Fs + fl 3 lFlb + 114 * Fl-C )° QzOI

- FzoI * QzO

where

QpOO1 is the quantity of debris reaching the

suppression pool (ft3)

QZoi is the quantity of insulation contained in

the zone of influence (ft3)

is the fraction of QZoi destroyed into

small pieces

12 is the fraction of QZoi destroyed into

large pieces, but generated above the

lowest floor grating

13 is the fraction of QZo I, destroyed into

large pieces, but generated below the

lowest floor grating

T14 is the fraction of QZoi destroyed into

large pieces covered in canvass

FZOI is the weighted average transport factor

that can be applied to the ZOI. This is

very similar to the transport factors

proposed by the BWROG [Ref. 5.1]

From the onset, the study did not focus on developing

the size distribution fractions applicable to each plant

type and postulated scenario. Instead, the study

focused on developing a flexible method by which the

analyst can easily input the size distribution fractions

deemed applicable to the particular scenario being

analyzed. To meet this objective, the logic charts were

configured such that applicable size distribution data

(i.e., l, 12, 113, and 114) can be directly entered into

them and the resulting values under the heading

'Fractions' can be summed to calculate FZOI.

To demonstrate this further, consider that a plant

wishes to use the BWROG recommended debris size

distribution listed in Table 5-1 and estimate the

quantity of debris transported to the suppression pool

for the accident scenario described in Section 4.1. For

the break under consideration, the plant layout

(Ref. 5.1) suggests that 90% of the large debris would

be generated above the lowest grating, with the

remainder generated below the lowest grating. For the

upper bound, however, the licensee estimates that 20%

of the large debris is generated below the lowest

grating, instead of the 10% used in the central estimate.

Assume that accident scenario and the plant geometry

under consideration is same as that described in

Section 4.1.

As shown in Table 5-1, for the central estimate, the size

distribution fractions, Ti, 12, 13, and 714, are equal to

0.22, 0.342 (0.38 x 0.9), 0.038 (0.38 x 0.1), and 0.4.

Similarly, for the upper bound estimate, il, 112, 113, and

14 are equal to 0.22, 0.304 (0.38 x 0.8), 0.076 (0.38 x 0.2),

and 0.4. The logic charts displayed in Figures 5-1 and 5-

2 were obtained from Figure 4-1 and 4-2, respectively,

by entering the upper bound and central estimates for

11i, 12, 13, and 1)44 in place of 1.0. Quantification results

for these two charts are shown in Table 5-2 and 5-3. As

shown in these tables, the upper bound estimate for

FZOI is 0.286, whereas the central estimate is 0.154.

Table 5-4 provides similar estimates for all the LOCA

scenarios

5-1 NUREG/CR-6369
Application of the Study Results

Table 5-1. Debris size distribution data used in example 1 Reference 5.1.

BWROG Distribution of Generated Debris

Debris Classification Upper Bound Central Estimate

Small Pieces 0.22 0.22

Large Pieces 0.38 0.38

Canvassed 0.40 0.40

Location of Large Pieces Relative to Lowest Grating

Debris Classification Upper Bound Central Estimate

Large Above 0.8 0.9

Large Below 0.2 0.1

Distribution for Logic Chart Quantification

Debris Classification Upper Bound Central Estimate

Small Pieces (in) 0.22 0.22

Large Pieces (Tb) 0.30 0.34

Large Pieces - Below (in) 0.08 0.04

Canvassed (n) 0.40 0.40

postulated in this study. As shown in this table, the

upper bound estimates for FZOI for a Mark I MSLB

between 0.28 and 0.31 depending on the scenario

considered. For a recirculation line break, FZOI

upper bound reached up to 0.4. Variations between

Mark I, II, and III are not significant because the

study assumed that all the containment types

contain two floor gratings and other plant features

that are similar.

In this example, the BWROG size distribution data

was used to demonstrate the ease with which such

data (if judged to be applicable) can be integrated

into the logic charts. Its use should not be perceived

as an unconditional endorsement of its applicability

to a variety of breaks. The analyst must judge its

applicability and, if not applicable, derive applicable

plant-, break- and insulation-specific size

distribution data for use.

5.2 Deviations from the Assumed

Generic Plant Geometry

As described in Section 4, all the logic charts

presented thus far have been based on certain

assumptions related to plant geometry. Direct use of

the transport factors presented in Table 5-4.

Appendix-A is only justified if the plant being analyzed

is similar to the assumed plant geometry. If not, any

variations should be carefully considered to derive

applicable transport factors. To demonstrate how such

variations can be accommodated, consider a Mark I

plant with one floor grating instead of two floor

gratings as assumed in the present case. For this case,

assume the same size distribution as that used in the

example above.

This deviation can be seen to affect distribution after

blowdown in Figures 5-1 and 5-2. Note that these

fractions were obtained by assuming two gratings as

shown in Figures 4-7 and 4-8. Retention at the upper

grating can be eliminated by setting capture efficiency

in both cases to be 0.0, instead of 0.15 used in Figure 4-7

and 0.25 used in Figure 4-8. As shown in Figures 5-3

and 5-4, this change results in transport of a higher

fraction of debris to the vents during blowdown.

Figures 5-5 and 5-6 present resulting logic trees for the

overall accident scenario, with the quantification results

presented in Tables 5-5 and 5-6. These tables, when

compared to Tables 5-1 and 5-2, clearly illustrate that a

larger fraction of the small debris would be transported

if the plant were to have a single grating.

NUREG/CR-6369 5-2
Application of the Study Results

Table 5-2. Upper bound estimates for debris transport based on BWROG size distribution data.

DEBRIS TRANSPORT RESULTS

Plant Design: MARK I

Estimate: UPPER BOUND FIBROUS INSULATION

Break: MSL BREAK

ECCS: ECCS THROTTLED

Sprays: SPRAYS OPERATED

TREE QUANTIFICATION

Debris Classification Vents Enclosures Floor Structures Structures Structures Transport Above Break Other Fraction

Small Pieces 1.982E-01 0.OOOE+00 2.178E-02 O.OOOE+00 0.OOOE+0 0 .OOOE+00 0.9010

Large Pieces-Above 6.OOOE-03 0 0.000E+00 0 7.350E-02 2.205E-01 0.0200

Large Pieces-Below 8.000E-02 0.OOOE+00 0.OOOE+00 0 0.OOOE+00 0.OOOE+00 1.0000

All 9rufe Pieces R tooFl-f 0n oooPFlo0 nomp±00 o 0 7 1l5fl-029 9.20F-flI 0 .263I ' '" E,- ' ' ---- v.uvv v v-v I--~ - 1 v , .S-v /_ -- Iva-v-- I1 U.SUz

All Debris 2.842E-0 I 0.OOOE+00 I 2.178E-02 0.OOOE+00 I 7.350E-02 I 2.205E-01 0.4737

All Zone-of-Influence 0.2842

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification Vents Enclosures Floor Structures Structures

Above I Break

tructures

Other

Small Pieces 90.10% 0.00% 9.90% 0.00% 0.00% 0.00%

Large Pieces-Above 2.00% 0% 0.00% 0% 24.50% 73.50%

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00% 0.00%

All Large Pieces 22.63% 0.00% 0.00% 0% 19.34% 58.03%

All Debris 47.37% 0.00% 3.63% 0.00% 12.25% 36.75%

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Above Brea Other

Above Break Other

Small Pieces 69.74% N/A 100.00% N/A 0.00% 0.00%

Large Pieces-Above 2.11% N/A 0.00% N/A 100.00% 100.00%

Large Pieces-Below 28.15% N/A 0.00% N/A 0.00% 0.00%

All Large Pieces 30.26% N/A 0.00% N/A 100.00% 100.00%

Debris Transport Fractions

1.250

1.000

C 0.750 0

.1

iL 0. 500

o.ooo

Small Debris Large Above Large Below All Large Debris

Gratings Gratings

All Debris All Zone-ofInfluence

5-3 N UREG/CR-6369
Application of the Study Results

Table 5-3. Central estimate for debris transport based on BWROG size distribution data.

DEBRIS TRANSPORT RESULTS

Plant Design: MARK I

Estimate: CENTRAL ESTIMA FIBROUS INSULATION

Break: MSLBREAK

ECCS: ECCS THROTTLED

Sprays: SPRAYS OPERATED

TREE QUANTIFICATION

Debris Classification Vents Enclosures Floor Structures Structures Structures Transport Above Break Other Fraction |

Small Pieces 1.149E-01 2.200E-03 4.803E-02 8.712E-03 I.IOOE-02 3.520E-02 0.5221

Large Pieces-Above 3.400E-03 0 O.OOOE+00 0 5.049E-02 2.861 E-0l 0.0100

Large Pieces-Below 3.600E-02 4.OOOE-04 1.620E-03 0 3.960E-04 1.584E-03 0.9000

All Large Pieces 3.940E-02 4.000E-04 1.620E-03 0 5.089E-02 2.877E-0 .

All Debris 1.543E-01 2.600E-03 4.965E-02 8.712E-03 6.189E-02 3.229E.-01 A,'71

All Zone-of-Influence 0.1543

FINAL DISTRIBUTIONS (Horizontal)

'V

Debris Classification Vents Enclosures Floor tructures

Above .Be ULLUR V . ucLureC

nfh-e

Small Pieces 52.21% 1.00% 21.83% 3.96% 5.00% 16.00%

Large Pieces-Above 1.00% 0% 0.00% 0% 14.85% 84.15%

Large Pieces-Below 90.00% 1.00% 4.05% 0% 0.99% 3.96%

All Large Pieces 10.37% 0.11% 0.43% 0% 13.39% 75.71%

All Debris 25.71% 0.43% 8.27% 1.45% 10.31% 53.82%

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Structures Structures Structures

IAbove Break Other

Small Pieces 74.46% 84.62% 96.74% 100.00% 17.77% 10.90%

Large Pieces-Above 2.20% 0% 0.00% 0% 81.59% 88.61%

Large Pieces-Below 23.34% 15.38% 3.26% 0% 0.64% 0.49%

All Large Pieces 25.54% 15.38% 3.26% 0% 82.23% 89.10%

Debris Transport Fractions

1.o0o

0.750 4 -- _

.o

Lw

0.500 I

0.250 -

0.000 Io

All Zone-ofInfluence

Small Debris Large Above Large Below All Large Debris

Gratings Gratings

All Debris

NUREG/CR-6369 5-4
Application of the Study Results

Table 5-4. Central and upper bound estimates for debris transport factors based on BWROG size distribution data.

DEBRIS TRANSPORT FRACTIONS

Break ECCS Sprays Small Large Above Large Below All Large All Debris All ZOI

Central UB Central UB Central UB Central UB Central UB Central UB

Mark I = = =

Main Steam Line Steaming Not Used 0.52 0.89 0.00 0.00 0.90 1.00 0.09 0.21 0.25 0.46 0.15 0.28

Main Steam Line Steaming Operated 0.52 0.90 0.01 0.02 0.90 1.00 0.10 0.23 0.26 0.47 0.15 0.28

Main Steam Line Full < 1 Hr Not Used 0.63 0.93 0.01 0.03 0.94 1.00 0.11 0.23 0.30 0.49 0.18 0.29

Main Steam Line Full < 1 Hr Operated 0.79 1.00 0.02 0.05 0.94 1.00 0.12 0.25 0.36 0.53 0.22 0.31

Recirculation Line Full < 1 Hr Not Used 0.74 1.00 0.01 0.12 0.94 1.00 0.11 0.31 0.34 0.56 0.21 0.34

Recirculation Line Full < 1 Hr Operated 0.86 1.00 0.02 0.12 0.94 1.00 0.12 0.31 0.39 0.56 0.23 0.34

Recirculation Line Full < 3 Hr Not Used 0.74 1.00 0.04 0.30 0.94 1.00 0.14 0.45 0.36 0.65 0.21 0.39

Recirculation Line Full < 3 Hr Operated 0.86 1.00 0.05 0.30 0.94 1.00 0.14 0.45 0.40 0.65 0.24 0.39

Mark II =

Main Steam Line Steaming Not Used 0.55 0.89 0.00 0.00 0.90 1.00 0.09 0.21 0.26 0.46 0.16 0.28

Main Steam Line Steaming Operated 0.74 1.00 0.01 0.02 0.90 1.00 0.10 0.23 0.34 0.51 0.20 0.31

Main Steam Line Full < 1 Hr Not Used 0.70 0.95 0.01 0.03 0.95 1.00 0.11 0.23 0.33 0.50 0.20 0.30

Main Steam Line Full <1 Hr Operated 0.83 1.00 0.02 0.05 0.95 1.00 0.12 0.25 0.38 0.52 0.23 0.31

Recirculation Line Full <1 Hr Not Used 0.80 1.00 0.01 0.12 0.95 1.00 0.11 0.31 0.36 0.56 0.22 0.34

Recirculation Line Full < 1 Hr Operated 0.89 1.00 0.02 0.12 0.95 1.00 0.12 0.31 0.40 0.56 0.24 0.34

Recirculation Line Full < 3 Hr Not Used 0.80 1.00 0.04 0.30 0.95 1.00 0.14 0.45 0.38 0.65 0.23 0.39

Recirculation Line Full < 3 Hr Operated 0.89 1.00 0.05 0.30 0.95 1.00 0.14 0.45 0.42 0.65 0.25 0.39

Mark Ill_

Main Steam Line Steaming N/A 0.55 0.89 0.00 0.00 0.90 1.00 0.09 0.21 0.26 0.46 0.16 0.28

Main Steam Line Full < 1 Hr N/A 0.64 0.93 0.01 0.03 0.90 1.00 0.11 0.23 0.30 0.49 0.18 0.29

Recirculation Line Full < 1 Hr N/A 0.72 1.00 0.01 0.12 0.90 1.00 0.11 0.31 0.33 0.56 0.20 0.34

Recirculation Line Full < 3 Hr N/A 0.72 1.00 0.04 0.30 0.90 1.00 0.13 0.45 0.35 0.65 0.21 0.39

5-5 NUREG/CR-6369
Application of the Study Results

LOCA Type |DebrisClassifcatio Advectdtow Distribution After Vn Erosion and Washdown Drywell Floor Pool I t Fraction | Final Location ._ A__________o

A --IfW.- I - - AVY9V;SV TU V UIIL; I I .958E-01 Ventc MARK I

UPPER BOUND

MSL BREAK

ECCS THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

I I . tt -nlV ., 0.89 . . Enclosures - ------------- _ 2 0.000E+00 Enclosures -lrr - - - - - - - - - - --- 4-- .uu

Waterbome 3 0.000E+00 VenLs ------------------- 3_ _ . A _+.4 V.n

Drywell Floor ___________________________________-

0.00

10.00

iSediment

1.00

Waterbome

. 4 0.000E+00 j Floor

5 0.000E+00 Vents S 0.OOOE+00 VentsCondensate Drainage

:0.10

Structures-Above i

0.00 -Adheres

6 0.000E+00 ;r----------_______

Small Pieces

10.22

7 O.OOOk+OO ---------- --- ---- --- --- 7--- 0.90

Waterborne 8 6.600E-04 Wat.vrvo. v 0.10

Sprays/Condensate

1.00 Sediment

Structures-Break 0.90

0.03 WAdheres

Floor

Structures-Above

Vents

Floor

Structures-Break

Vents

9

9n

5.940E-03

,__ __ _____ _________ _____________---- __ . v 0.OOOE3+00 0.00

Waterbome I1I _

0.10

Sprays/Condensate

1.00 Sediment

Structures-Other 0.90

0.08 Adheres

: 12 I .584E-02 Floor

1 3 0.000E.+00 Sh^lchlrec Other

Structures-Break

0.25

Large-Above

0.30

Structures-Other

0.75

Advected to Vent

0.00 ------------- ---- _vvv--- Waterbome 14 1.500E-03 Vents

Sprays/Condensate

0.02 ;Sediment is 0.OOOE+00 Floor

LAdheres 16 7.350E-02 Structures-Break

0.98

Waterbome 17 4.500E-03 Vents

1.00

Sprays/Condensate

0.02 ISediment 18 0.OOOE+00 Floor

Adheres 19 2.205E-01 Structures-Other MSL Break

1 00 -1. I (I A .nnn. n? VAA+-

1.00 I I o.uuur - vets

Large-Below |EncLosures _ _________________ 21 j 0.OOOE+00 J _ Enclosures

0.08

'Drywell Floor

Waterbome

'0.00

Seimn

22 O.OOOE+00 Vents

f 7' - 77 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ;0.00 23 O.OOOE+00 Floor

1.00

Waterborne 24 O.OOOE+00 Vents

TSediment 25 0.OOOE+00 Floor

Sprays/Condensate

'0.02

Structures-Break I

0.00 -Adheres 1.00

26 n nnnr-n ! ...--------I---------------- -_ ------- _ _ Structures-Break

Vents

U.Y8

Waterborne 27 O.OOOE+00 -------- _ _- ,I _. i0.00 --

Sprays/Condensate I

1 ;0.02 --- Sediment

iStructures-Other I '1.o00 -- ' 0.00 IAdheres

Vents

28 O.OOE00pn Flnn ---- ...-----

29 O.OOOE+00 Stmehlreq nthPr

n _, - - -- - --------------- u.ve

Canvassed n A nnnfl nr cs S . _ _ _ _ n^r

n j _ -_ '.vuuuo-vu, Sutrctusres/toor

u08u _ . Total_4i _.000F 0

Figure 5-1. Upper bound logic chart with bWhkit size dUSLisDuttioji data.

NUREG/CR-6369 5-6
Application of the Study Results

Casfcdl Distribution After pathI

LOCA Type Debris Canfcd i Erosion and Waslhdown Dryweli Floor Pool No FrActfon Final Location

Advected to Vents I 1.144E-0 Vents

MARK I

CENTRAL ESTIMATE

MSL BREAK

ECCS THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

Small Pieces

r0.22

E.lsue 2 2.200E-03 Enclosures

0.01

Waterbome 3 0.000E+00 Vents I-- --- --------- ! i0.00

Drvwell Floor_., _ _. .. 0.01 I SSediment 4 2.200E-03 Floor

1.00

Waterbome 5 1 8.800E-07 I Vents

0.01 I i

I I

ISedimet 1 6 8.712E-05 ! Floor

Condensate Drainage

0.01

Structures-Above

2.04 Adheres

0.99 7 S.712E-03 Stractures-Above

0.99

Waterbome 8 1.100E-04 Vents

0.01

Sprays/Condensate

0.50 Sediment

Structures-Break 0.99

0.10 Adheres

0.50

i

I i

t 9 | t.089E-02 Fioor

10 I.1 00E-02 i Structures-Break _ W il

Waterborme II 3.520E-04 Vents

0.01

Sprays/Condensate

0.50 Sediment

Structures-Other 0.99

A 11 IAdheres

I I

! 12 3.485E-02 Floor

13 3.520E-02 Structures-Other p.,

Structures-Break

0.15

Large-Above

0.34

Structures-Other

0.85

Advected to Vent

0.50 1 I Watetborme 14 5.100E-04 Vents

Sprays/Condensate

001 Sediment 15 0.000E+00 Floor 0.01 __------------1 0.00

_Adheres 16 5.049E-02 Structures-Break

0.99

Waterboome 1 7 2.890E-03 Vents

11.00

Sprays/Condensate

0.01 Sediment 18 0.000E+00 Floor

0.00 ' S t -

_Adheres 19 2.861E-01 Structures-Othser

MSL Break

1.00

0.99 20 3.600E-02 Vents

).90

Enclosures 21 1 4.000E-04 Enclosures

Large-Below

0.04

Canvassed

).01 Waterborne ! 22 O.OOOE+00 Vents

------- __ __ __ - -- __

i0.00

Drywell Floor 1.600E-03 0.04 ISediment 23 Floor

.1.00 i

Waterbome . 24 10 000E+00 Vents

'0.00 Ii

Sediment ; 25 4.OOOE-06 Floor

SpraystCondensate

0.01

Structures-Break

0.01 Adheres

1.00

26 3.960E-04 Structures-Break .

_

0.99

Waterbome 27 0.000E+00 Vents

'000 ____-. i0.00

Sprays/Condensate

0.01 Se!diment

Structures-Other 1.00

0.04 Adheres

28 ] 1.600E-05 Floor

I 29 1 1.584E-03 Structures-Other

0.99 _ 30 4.000E-01 i Structures/FIoor -

Toisl I 000Fv00 n a, Tota I 000F+60

Figure 5-2. Central estimate logic chart with BWROG size distribution data.

5-7 5-7 NUREG/CR-6369
Application of the Study Results

Initiating Event Surface Wetting Distribution in Interaction with Interaction with Interaction with Path Fraction To Vent Location of Debris

Drywell Upper Grating Lower Grating Vent Structures

and Floor

Incomplete I 3.5000E-01 X Transported Into Vent

0.35 1---Downcomers | BWR MARK I Goes by 2 2.2653E-01 X Transported Into Vent

UPPER BOUND ESTIMATE Goes by .00 Downcomers

Goes By 0.85 LCaptured 0. 0000E00 Deposited onto Floor Near Vents

Small Pieces Upper Region 1.00 Captured 3.9975E-02 Structures Below Spray Heads

1.00 0.41 0.15

Captured 5 0.OOOOEOO Structures Below Spray Heads

Goes By 6 2.0443E-01 X Transported Into Vent

Complete Goes By 1.00 Downcrers

0.65 Middle Region 0.85 Captured 7 0.OOOOEOO

0.37 Captured 3.6075E-02

Goes by 9 1.4300E-01 X Trasported Into Vent

Lower Region |1.00 Downcomer

0.22 LCaptured 0. OOQEO _ Deposited onto Floor Near Vents 1 0

Figure 5-3. Effect of upper floor grating on upper bound estimate of debris distribution after blowdown.

NUREG/CR-6369 5-8
Application of the Study Results

Debris Size Distribution Distribution in Interaction Interation Interaction Interaction Interaction Interaction Path Fraction To Vent Location of Debris

Classification at Time of Drywell with with Upper with with Lower with with Vent

Vent Structures in Grating Structures in Grating Structures in Structures

Clearance Upper Middle Lower and Floor

Region Region Region

Structures (Above) 1 2.OOOOE-02 Structures Above Spray

0.02 Heads

Structures (Below) 2 8.0000E-02 Structures Below Spray

0.08 Heads

Enclosures 3 1.OOOOE-02 Enclosures

0.01

Goes By 1.9751 E-01 X Transported Into Vent

Goes By 10.99 4Downcomers

|BWR MARKT - Goes B 0 Catured 5 1.9951 E-03 Deposited onto Floor Near 0 75 0.01 Vents

GoES B y . Captured 6 2.2168E-02 Structures Below Spray

l ElE 0.90 0.10 Heads e Goes By Captured 7 7.3892E-02 Structures Below Spray Small1.00 0.25 Heads

1.00 Goes By Captured 8 3.2841 E-02 Structures Below Spray

0.90 0.10 Heads

Captured 9 O.OOOOEOO Structures Below Spray

Upper Region Heads

0.41 Captured (Above) 10 1 .8245E-02 Structures Above Spray

0.05 Heads

Captured (Below) 1 1 .8245E-02 Structures Below Spray

0.05 Heads

Goes By 12 1.9805E-01 X Transported Into Vent

Goes By 10.99 Downcomers

Goes B 0.90 Captured 13 2.0005E-03 Deposited onto Floor Near

13 1Vents Airboe Go751 Captured 2.2228E-02 Structures Below Spray

0.89 Goe Y 0.10 1Heads

Middle Region Captured 15 7.4092E-02 Structures Below Spray

0.37 0.25 Heads

Captured 16 3.2930E-02 Structures Below Spray

0.10 Heads

Goes B 17 1.7446E-01 X Transported Into Vent

Goes By 0.99 Downcomers

Lower Region 0.90 Captured 18 1.7622E-03 Deposited onto Floor Near

0.22 0.01 Vents

Captured 19 1 .9580E-02 Structures Below Spray

0.10 Heads

Figure 5-4. Effect of upper grating on central estimate of debris distribution after blowdown.

5-9 5-9 NUREG/CR-6369
Application of the Study Results

LOCA Type Debris Classiicato Distribution After Erosion and Washdown Drywell Floor Pool I N I Fraction | Final Location I lsilaii Blowdown IINo. I

MARK I

UPPER BOUND

MSL BREAK

ECCS THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

NO UPPER CRATING

Small Pieces

10.22

. Uveucla I--- I~n LU -A/D+ --. VemLS .. I 1 1_ SA- F I 2.U24E-U1 Vents

0.92 2

Enclosures - 2 I .OOOE+00 j Enclosures *A AA--- -------------- -------- 4- +I2!000+0IEcoue 0.00

Waterborne 3 0.OOOE+00 Vents

iO.0_

Drywell Floor

0. °° Sediment

1.00

Waterbor.

I ;0.10 Condensate Drainage

10.10 tSediment

Structures-Above I 0.90

0.00 mAdheres

- --- -- --

4 0.OOOE+00 Floor

re - | 5 0.OOOE+00 Vents

t 6 0.OOOE+00 Floor

7 0 .OOOk+00 Structures-Above ------------------------------------ - - I 0.90

Waterbome 8 4.400E-04 Vents

0.10

Sprays/Condensate

1.00 Sediment

Structures-Break | 0.90

0.02 iAdheres

I . . _loor I 

t| 9 3.960E-03 | Floor

10 0.OOOE+00 Structures-Break ,-- __ ___ ___------i-- -I 0.00

Waterborne II I .320E-03 Vents

10.10

Sprays/Condensate |

1.00 Sediment

Structures-Other 0.90

0.06 ,Adheres

2 l F

t 12 1.18E0 Floor

13 0.OOOE+00 Structures-Other

Structures-Break

d o0.2 V

|Large-Above

Structures-Other

1 0.75

| Advected to Vent

-- -- -- -- -- -- - -------------- I

Waterbome 14 1.500E-03 Vents

Adheres |16 7.350E-02 Structures-Break

0.98

Waterborne 17 4.500E-03 Vents

Sprays/Condensate

0.02 1Sediment 18 0.OOOE+00 Floor

0.00

lAdheres 19 2.205E-01 Structures-Other MSL Break

1.00

0.98

20 8.000E-02 Vents

1.0 1I r ° I -----

t2LEnclsrs ------------------ --- 2 1 IOOOOE+00 I Enclosures

10.00 .-

Large-Below

0.08

!Drvwell Floor

Waterbome 22 0.OOOE+00 Vents

ei0 en

:0.00 !Sediment 23 0.OOOE+00 Floor

1.00 - -

Waterborne 24 0.OOOE+00 I Vents

I10.00 ._______________ _ lo

'Sediment 25 0.000E+00 Floor __ ___ __-- - - - - - - - - - -___ ___ __--_

Sprays/Condensate

'0.02

Structures-Break I

.0o -- Adheres 1.00

26 0.OOOE+00 Structures-Break !________ __ _ _ - ___- I - _ A 0.98

Waterbome 27 0.OOOE+00 Vents

:0.00

Sprays/Condensate I

: ;0.02 - Sediment

|Structures-Other i 0

0.00 tAdheres

: 28 0.OOOE+00 Floor

29 0.000E+00 Structires-Other ...-- 9 vvvv 4 -- .I--- --- v- 0.98

Canvassed 30 4.000E-01 tratuhres/Floor I - - - - -_ .-

U.40. . I -_ . -

v~~~vulv Io:I.OFO

Figure 5-5. Upper bound logic tree for debris transport in a Mark I drywell wiLth one floor grating.

NIJREG/CR-6369 5-10
Application of the Study Results

=istribuo n Aftr i and W=down Drywell Floor Pool I ath Fraction Flnal Location

. . _._ I t 2C F V...

Advected to Vents i.L:rUX tu

MARK I

CENTRAL ESTIMATE

MSL BREAK

ECCS THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

NO UPPER GRATING

Small Pieces

0.22

Large-Above

0.34

SL Break

1.00

Encl~osures 2 2.200E-03 I Enclo~sue

1 ; t 3.01 Watebomre 3 o.oooE+00 Vents ------- ------- I .

,0.00

Drywell Floor _., _ __. .. j

0.01 R Sediment 4 2.200E-03 Floor ___ ___ __ 4 +.___

1.00 1

Waterbome 5 8.SOOE-07 Vents

0.01 1

I Sediment I 8.712E-05 Floor Condensate Drainage

0.01

Structures-Above

0.04 Adheres

0.99 7 8.712E-03 Structures-Above

; -1 I

0.99 Waterbome 9.900E-05 Vents 8

0.01

Sprays/Condensate

0.50 Sediment

Structures-Break 0.99

0.09 Adheres

9 9.801 E403 Floor I

10 9.900E-03 Shructures-Break

_ ! 0.50 Waterbome II 3.080E-04 Vents

0.01

Sprays/Condensate

0.50 Sediment

Structures-Other 0.99

0.28 Adheres

_- I. I

t 12 1 3.049E-02 Floor

13 3.080E-02 Structures-Other

0.5

Sprays/Condensate

0.01

Structures-Break Ades

0.15 Aiee

0.99

_ Sprays/Condensate

0.01

Structures-Oher

0.85 Adheres

0.99

Adece toD Vent

Waterbome 14 5. IOOE-04 Vents

1.001

iSediment is O.wwE+0w Floor I---------------- ,

16 5.049E-02 Structures-Break

Waterbome 17 2.890E-03 I Vet

1.0 I IF I

is I 0.OwOE+00 I Flo

0.00 I Structure 19 2.86tE401 __________

its

0

or

Db

20 3.600E-02 Vel

-Other

I

am

... : , I

).90 1 21 4 wOE-04 Enclos

Enclosures .

Large-Betlow

0.04

Canvassed

3.01 Waterbome 22 0.OwOE+00 Veni

,O.w0

Drvwell ., _ _ 

Floor....... _ I

0.04 _ Sediment 23 1.600E-03 Floor

1.00 I

Waterboore 24 | O.wwE+w 1 Vents _________ :_

10.00 7

'OwI I I

eiment ! 25 4.0wE-06 r Floor Sprays/Condensate

0.01

Structurs-Break

0.01 Adhrexs

0.99

I .w

26 3.960E-04 Structums-Break j I

Waterbornne 27 0.000E+00 Vents

i0.00

Sprays/Condensate i

Structures-Other 100

0.04 Adheres

-- ------- i

21 2 1.600E-05 Floor

1 29 1.584E-03 Structures-Other

30 ! 4.0wE-01 . Structures/Floor

0.9 0.99

o 40 I -. I .

Figure 5-6. Central estimate logic tree for debris transport in a Mark I drywell with one floor grating.

5-11 NUREG/CR-6369
Application of the Study Results

Table 5-5. Upper bound transport factors for debris transport in a Mark I drywell with one floor grating.

DEBRIS TRANSPORT RESULTS

Plant Design: MARK I

Estimate: UPPER BOUNDDFIROUSNINULATION

Break: MSL BREAKE

ECCS: ECCS THROTTLE

Sprays: SPRAYS OPERATED

TREE QUANTIFICATION

Debris Classification Vents Structures Structures Structures Transport

Above Break Other Fraction

Small Pieces 2.042E-01 0.000E+00 1.584E-02 0.OOOE+00 I O.OOOE+00 I 0.OOOE+00 I 0.9280

Large Pieces-Above I03 0 1 0.OOOE+00 [ 0 7.350E-02 2.205E-01 ( 0.0200

Large Pieces-Below 0.0 ,+001 0.0

1.1 I=w 7

-00

All Large Pieces

0

0

A nnrnFl4nn

1.0000

0.2263

0.4836

n 1-n

All Debris

All Zone-of-Influence

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification Vents Enclosures Floor [ructures Itructures

Above Break

Structures

Other

Small Pieces 92.80% 0.00% 7.20% 0.00% 0.00% 0.00%

Large Pieces-Above 2.00% 0% 0.00% 0% 24.50% 73.50%

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00% 0.00%

All Large Pieces 22.63% 0.00% 0.00% 0% 19.34% 58.03%

All Debris 48.36% 0.00% 2.64% | 0.00% 1 12.25% 36.75%

RELATIVE CONTRIBUTIONS (Vertica

Debris Classification Vents Enclosures Floor Above Break Otheru |

Small Pieces 70.36% N/A 100.00% N/A 0.00% 0.00%

Large Pieces-Above 2.07% N/A 0.00% N/A 100.00% 100.00%

Large Pieces-Below 27.57% N/A 0.00% N/A 0.00% 0.00%

All Large Pieces 29.64% N/A 0.00% N/A 100.00% 100.00%

Debris Transport Fractions

1.250

1.000

C_ 0

Ut

U0.750 e0.500 -I0.250 4--

0.000 - .Sa.l...eb I

Sm211 Debris

_ -- -- -- r ----- _ , --- ...- - - -'1 . -'- -'- -''- - 1 '--'---.

s Large Above Large Below All Large Debris

Gratings Gratings

1

All Debris All Zone-ofInfluence

NUREG/CR-6369 5-12
Application of the Study Results

Table 5-6. Central estimate transport factors for debris transport in a Mark I drywell with one floor grating.

DEBRIS TRANSPORT RESULTS

Plant Design: MR

Estimate:CETAESIAEBOSIUAT N

Break: MSL BREAK

ECCS: ECCS THROTTLED

Sprays: SPRAYS OPERATED

TREE QUANTIFICATION

Debris Classification Vents Enclosures Floor Structure ra Stru ctures Transpo Above Break Other Fraction

Small Pieces j .258E-01 2.200E-03 4.258E-02 8.712E-03 9.900E-03 3.080E-02 0.5719

Large Pieces-Above 3.400E-03 0 O.oOOE+00 0 5.049E-02 2.861E-01 0.0100

Large Pieces-Below 3.600E-02 4.000E-04 1.620E-03 0 3.960E-04 1.584E-03 0.9000

All Large Pieces

All Debris

All Zone-of-Influence

FINAL DISTRIBUTIONS (Horizontal) p p -

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris I-IRELATIVE CONTRIBUTIONS (Vertical)

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

Debris Transport Fractions

1.000

0.750

U. 2

0.500 --_

0.250

0.000

.

Small Debris

i Il _ l I *_

Large Above Large Belw

Gratings Gratings

All Large Debris All Debris All Zone-ofInfluence

5-13 NUREG/CR-6369
Application of the Study Results

A variety of deviations from assumed plant

geometries can be analyzed by simply altering

appropriate branch ratios, including assumptions

related to operation of containment sprays, break

overflow duration and drywell floor design.

5.3 References

5.1 NEDO-32686, "Utility Resolution Guidance

for ECCS Suction Strainer Blockage," Boiling

Water Reactor Owners' Group, 1996.

5.2 U.S. Nuclear Regulatory Commission, "Water

Sources for Long-Term Recirculation Cooling

Following a Loss of Coolant Accident,"

Regulatory Guide 1.82, Rev. 2, 1995.

5.3 Zigler et al., "Parametric Study of the Potential

for BWR ECCS Strainer Blockage Due to LOCA

Generated DEBRIS," NUREG/CR-6224,

Science and Engineering Associates, Inc., 1995.

5.4 D. V. Rao et al, "Drywell Debris Transport

Study: Experimental Work," NUREG / CR6369, Supplement 1, Science and Engineering

Associates, Inc., 1997

NUREG/CR-6369 5-14
Appendix A

Compilation of Debris Transport Study Logic Charts
Appendix A

A.1 INTRODUCTION

The drywell debris transport problem was decomposed into several components that were amenable to

resolution by the available knowledge base including small-scale experiments, analytical modeling and

engineering calculations, and by engineering judgments. Then the solutions to the individual components

were linked together into a comprehensive study using logic charts the represented the overall transport

process. A separate chart was created for each accident scenario and each plant design analyzed but

only selected logic charts were presented in the main document of this report. This appendix provides, in

Sections A.3 and A.4, a complete compilation of the charts for the reader desiring detailed information.

The quantification results for all the charts are presented in Section A.2.

The structure of the logic chart, which was identical for each of the scenarios and plant design studied,

was explained in the main document (see Figure 2-9). To summarize, the charts decomposes the overall

transport problem into those transport processes associated with primary system blowdown, subsequent

erosion and washdown of the insulation debris deposited onto structures during the blowdown period, and

the water pool forming on the drywell floor. The chart further treated small debris separately from large

debris and large debris still encased in the canvas cover. Further, large debris was subdivided into large

debris generated above any grating and large debris generated below the lowest grating. The relative

concentrations of small and large debris were essentially an unknown to this study and their

determination was not a study objective. Therefore, the results are reported by debris size classification

and then combined with debris generation data from an outside source to illustrate how this data can be

used to determine overall debris transport fractions. The first sheet of each logic charts contains the

actual structure of the chart while the second sheet contained the tabulated results for that chart. The

identification of the accident scenario and the plant design is found in the upper left comer of each sheet.

The logic chart structure (first sheet) begins at the left side and then progresses from left to right as the

insulation debris was postulated to move through the various transport processes. The structures

resulted in a total of 30 separate debris transport pathways with the fraction of the initial debris following

each pathway and its final location noted in the right two columns. Note that that sum of the fractions

adds to one.

Three tables of quantification results are shown on each of the second sheets along with a graphical

presentation of the transport fractions. The first of these three tables shows a summation of the debris

fraction sorted by debris type and their final locations. The fractions of debris transported into the

downcomer vents are shown in the column at the right. For example, the transport fraction for small

debris in the right column was the predicted fraction of the debris in the form of small pieces that was

transported into the vent downcomers. The debris classifications in the first table are further illustrated in

Table A-1.

Table A-1: Basis for Quantification of Debris Transport by Debris Classification

Debris Classification Basis for Quantification

Small Pieces Only small pieces of debris

Large Pieces-Above Only large debris generated above any grating.

Large Pieces-Below Only large debris generated below the lowest grating.

All Large Pieces The combination of both large pieces-above, and large

pieces-below.

All Debris The combination of small pieces, large pieces-above, and

large pieces-below.

All Zone-of-Influence All insulation contained in the zone-of-influence including

canvassed debris and intact insulation still on the pies.

The second and third of these tables contains the same information as the first table but the information is

expressed in percentages. In the second table, the percentages were based on the total fractions for that

debris classification (horizontal) and in the third table, the percentages were based on the total fractions

for a particular final location (vertical).

A-1 NUREG/CR-6369
Appendix A

A.2 COMPILATION OF RESULTS

The final quantification results are shown in Tables A-2 and A-3, and Figure A-1 through A-6. Table A-2

lists the debris transport fractions sorted by debris classification and scenario. Table A-3 shows the

relative contribution each debris classification made to the total debris transported into the downcomer

vents, i.e., the percentages for small, large-above, and large-below add to 100%. Figure A-1 shows the

transport fractions for small debris alone in a bar chart for each scenario for the Mark I design. Figure A-2

shows the transport fractions combined with a debris generation size distribution, i.e., fraction of all

insulation located in the total zone-of-influence that transported into the vent downcomers for a Mark I

design. The other figures, Figures A-3 through A-6, show similar results for the Mark II and IlIl designs

NUREG/CR-6369 A-2
I

~0

Table A-2: Debris Transport Fractions

DEBRIS TRANSPORT FRACTIONS

Small Large Above Large Below All Large All Debris All ZOI

Break ECCS Sprays

Central UB Central UB Central UB Central UB Central UB Central UB

Mark I . =

Main Steam Line Steaming Not Used 0.52 0.89 0.00 0.00 0.90 1.00 0.09 0.21 0.25 0.46 0.15 0.28

Main Steam Line Steaming Operated 0.52 0.90 0.01 0.02 0.90 1.00 0.10 0.23 0.26 0.47 0.15 0.28

Main Steam Line Full < 1 Hr Not Used 0.63 0.93 0.01 0.03 0.94 1.00 0.11 0.23 0.30 0.49 0.18 0.29

Main Steam Line Full < 1 Hr Operated 0.79 1.00 0.02 0.05 0.94 1.00 0.12 0.25 0.36 0.53 0.22 0.31

Recirculation Line Full < 1 Hr Not Used 0.74 1.00 0.01 0.12 0.94 1.00 0.11 0.31 0.34 0.56 0.21 0.34

Recirculation Line Full < 1 Hr Operated 0.86 1.00 0.02 0.12 0.94 1.00 0.12 0.31 0.39 0.56 0.23 0.34

Recirculation Line Full < 3 Hr Not Used 0.74 1.00 0.04 0.30 0.94 1.00 0.14 0.45 0.36 0.65 0.21 0.39

Recirculation Line Full < 3 Hr Operated 0.86 1.00 0.05 0.30 0.94 1.00 0.14 0.45 0.40 0.65 0.24 0.39

Mark II

Main Steam Line Steaming Not Used 0.55 0.89 0.00 0.00 0.90 1.00 0.09 0.21 0.26 0.46 0.16 0.28

Main Steam Line Steaming Operated 0.74 1.00 0.01 0.02 0.90 1.00 0.10 0.23 0.34 0.51 0.20 0.31

Main Steam Line Full < 1 Hr Not Used 0.70 0.95 0.01 0.03 0.95 1.00 0.11 0.23 0.33 0.50 0.20 0.30

Main Steam Line Full < 1 Hr Operated 0.83 1.00 0.02 0.05 0.95 1.00 0.12 0.25 0.38 0.52 0.23 0.31

Recirculation Line Full < 1 Hr Not Used 0.80 1.00 0.01 0.12 0.95 1.00 0.11 0.31 0.36 0.56 0.22 0.34

Recirculation Line Full < 1 Hr Operated 0.89 1.00 0.02 0.12 0.95 1.00 0.12 0.31 0.40 0.56 0.24 0.34

Recirculation Line Full < 3 Hr Not Used 0.80 1.00 0.04 0.30 0.95 1.00 0.14 0.45 0.38 0.65 0.23 0.39

Recirculation Line Full < 3 Hr Operated 0.89 1.00 0.05 0.30 0.95 1.00 0.14 0.45 0.42 0.65 0.25 0.39

Mark Ill

Main Steam Line Steaming N/A 0.55 0.89 0.00 0.00 0.90 1.00 0.09 0.21 0.26 0.46 0.16 0.28

Main Steam Line Full < 1 Hr N/A 0.64 0.93 0.01 0.03 0.90 1.00 0.11 0.23 0.30 0.49 0.18 0.29

Recirculation Line Full < 1 Hr N/A 0.72 1.00 0.01 0.12 0.90 1.00 0.11 0.31 0.33 0.56 0.20 0.34

Recirculation Line Full <3 Hr N/A 0.72 1.00 004 0.30 0.90 1.00 0.13 0.45 0.35 0.65 0.21 0.39 _ __ < -Fll -H- - - -- 0 -2-

A-3
Table A-3: Relative Contributions to Transport into Vents

RELATIVE CONTRIBUTIONS TO TRANSPORT TO VENTS

Break ECCS Sprays Small Large Above Large Below All Large

Central UB Central UB Central UB Central UB

Mark I .

Main Steam Line Steaming Not Used 76% 71% 0% 0% 24% 29% 24% 29%

Main Steam Line Steaming Operated 74% 70% 2% 2% 23% 28% 26% 30%

Main Steam Line Full < 1 Hr Not Used 77% 70% 2% 3% 21% 27% 23% 30%

Main Steam Line Full < 1 Hr Operated 80% 70% 3% 4% 17% 26% 20% 30%

Recirculation Line Full < 1 Hr Not Used 80% 65% 2% 11% 18% 24% 20% 35%

Recirculation Line Full < 1 Hr Operated 81% 65% 3% 11% 16% 24% 19% 35%

Recirculation Line Full < 3 Hr Not Used 76% 56% 6% 23% 18% 21% 24% 44%

Recirculation Line Full < 3 Hr Operated 78% 56% 7% 23% 16% 21% 22% 44%

Mark II

Main Steam Line Steaming Not Used 77% 71% 0% 0% 23% 29% 23% 29%

Main Steam Line Steaming Operated 80% 72% 2% 2% 18% 26% 20% 28%

Main Steam Line Full < 1 Hr Not Used 79% 70% 2% 3% 19% 27% 21% 30%

Main Steam Line Full < 1 Hr Operated 80% 70% 3% 4% 17% 26% 20% 30%

Recirculation Line Full < 1 Hr Not Used 81% 65% 2% 11% 17% 24% 19% 35%

Recirculation Line Full < 1 Hr Operated 81% 65% 3% 11% 16% 24% 19% 35%

Recirculation Line Full < 3 Hr Not Used 77% 56% 6% 23% 17% 21% 23% 44%

Recirculation Line Full < 3 Hr Operated 78% 56% 7% 23% 15% 21% 22% 44%

Mark Ill

Main Steam Line Steaming N/A 77% 71% 0% 0% 23% 29% 23% 29%

Main Steam Line Full < 1 Hr N/A 78% 70% 2% 3% 20% 27% 22% 30%

Recirculation Line Full < 1 Hr N/A 80% 65% 2% 11% 18% 24% 20% 35%

Recirculation Line Full < 3 Hr N/A 76% 56% 7% 23% 17% 21% 24% 44%

nQ

U.) Mof0

A-5
oQ

ov

&D

Mark I Transport Fractions for Small Debris

1.0000

C

0

U

(a

L.. UIo

CL

(A

I0.7500

0.5000

0.2500

0.0000 IH IH IH

Throttled,

w/o

Sprays

Throttled,

with

Sprays

NVEL, %bt

Throttled,

w/o

Sprays

[VEL, Nbt

Throttled,

with

Sprays

RL,

Throttled,

w/o

Sprays

RL,

Throttled,

with

Sprays

R, Nbt

Throttled,

w/o

Sprays

RL, bt

Throttled,

Sprays

LOCA Scenario

Figure A-1: Mark I Transport Fractions for Small Debris

A-6
Nark I Combined Generation and Tranqort Fractions

1.0000

0

0

LL

0.

CL

(U)

L..

0.7500

0.5000

0.2500

0.0000

AEL,

Throttled,

w/o

Sprays

A/EL, M31L,l bt N43L, %t RL, FL, FL, Nbt

Throttled, Throttled, Throttled, Throttled, Throttled, Throttled,

with w/o with w/o with w/o

Sprays Sprays Sprays Sprays Sprays Sprays

FL, Nbt

Throttled,

Sprays

!E LOCA Scenario

Figure A-2: Mark I Combined Generation and Transport Fractions

A-7
~D

110

d

%a. r<,

Mark 11 Transport Fractions for Small Debris

m Central * Upper Bound

1.0000

e

0

UI I0

(a

0.7500

0.5000 -

0.2500 -

0.0000 - IH

EVSL,

Throttled,

w/o

Sprays

fVSL,

Throttled,

with

Sprays

A/EL, Nbt

Throttled,

w/o

Sprays

fSL, Not

Throttled,

with

Sprays

FL,

Throttled,

w/o

Sprays

FL,

Throttled,

with

Sprays

FL, Not

Throttled,

w/o

Sprays

FL, ot

Throttled,

Sprays

LOCA Scenario

Figure A-3: Mark 11 Transport Fractions for Small Debris

A-8
Mark 11 Combined Generation and Transport Fractions

1.0000

a

0

C._

(U

L.

Uen0

0.

UI0.7500

0.5000

0.2500

0.0000

KAL,

Throttled,

w/o

Sprays

IV/EL, IVEL, Not IVBL, Not LRL, RL~, RL, No

Throttled, Throttled, Throttled, Throttled, Throttled, Throttled,

w ith w/o w ith w/o w ith w/o

Sprays Sprays Sprays Sprays Sprays Sprays

FL, ot

Throttled,

Sprays

ni ;O&I W0 O

LOCA Scenario

Figure A-4: Mark 11 Combined Generation and Transport Fractions ,>la1

A-9
Mark III Transport Fractions for Small Debris

la Central * Upper Bound

1 .0000'

0.7500 a

0

a

UV

0

CL

u0

Ir0.5000 -

0.2500 -

0.0000 -

MSL, Throttled MSL, Not Throttled RL, Throttled RL, Not Throttled

LOCA Scenarios

Figure A-5: Mark IlIl Transport Fractions for Small Debris

A-10
Mark III Combined Generation and Transport Fractions

1.0000

0.7500

0

o

L.

LL

0

0.

U1)

C: (a

L..

0.5000

0.2500

0.0000

IVSL, Throttled MSL, Not Throttled RL, Throttled RL, Not Throttled

'0%

\.Ds

LOCA Scenarios

Figure A-6: Mark III Combined Generation and Transport Fraction

lid

CD

A-11
Appendix A

A.3 LOGIC CHARTS FOR CENTRAL ESTIMATES

The logic charts for the central debris transport estimates are presented here and the corresponding

upper bound estimates are presented on Section A.4.

A.3.1 Mark I

This section contains the central estimate logic charts for the Mark I design.

A.3.1.1 Main Steam Line Break

The central estimate logic charts for the main steam line breaks are presented here, then the charts for

the recirculation line breaks are presented in Section A.3.1.2

A-1 3 NUREGICR-6369
Appendix A

LOCA Type Debris Classlficado, Distribution AfterI Erosion and Washdown Drywell Floor Pool Pat Fraction J Final Location

II Blowdown I INo.II - ---- I.-11 -- - Advmc=a to vents I I. 144E-01 Venls

MARKI

CENTRAL ESTIMATE

MSL BREAK

ECCS THROTTLED

NO SPRAYS

FIBROUS INSULATION

Eo e 2 I Enclosures

U.OI

Waterborne 3 0.000E+00 Vents - - - - - - - - - - _ I - -__

Drywell Floor

10.00

i

0.01 ISediment 4 2.200E-03 Floor

Waterborne 5 0.OOOE+00 Vents

in0.00

lbedimen5 6 8.800E-05 Floor

Condensate Drainage

0.01

Structures-Above

D.04 Adberes Small Pieces

10.22

1.00

7 8.712E-03 Structures-Above + * 0.99

Waterborne 8 0.000E+00 Ventb

iO.OO

Condensate Drainage a

0.01 Sediment

Structures-Break 1.00

0.10 Adheres

t 9 2.200E-04 Floor

10 2.178E-02 Structures-Break 4 . I.

0.99

Watevborne II 0.000E+00 Vents

;0.00

Condensate Drainage I

0.01 Sediment

Structures-Other 1.00

0.32 Adheres

t 12 7.040E44 Floor

13 6.970P-02 Structures-Other

Structures-Break

0.15

Large-Above

0.34

Structures-0ther

0.8S

Advected to Vent

0.99

Waterborne 14 0.000E+00 Vents

10.00

Condensate Drainage 1

Wm iSediment 15 0.000E+00 Floor

1.00

Adheres 16 5.100E-02 Structures-Break

1.00

Waterborne 17 0.000E+00 Vents ,_________________

I10.00

Condensate Drainage I

la.oo Sediment 18 0.OOOE+00 Floor

I 9c1.00_

n~hrs19 2.890E401 Structures-Other

MSL Break

1.00

1.00

20 3.600E4O2 Vents

Enclosures 21 4.000E-04 I Enclosures

large-Below

0.04I

0.01

Waterborne 22 O.OOOE+00 Vents ,___________I_ I. I

DsyweH Floor

10.00

0.04 1Sediment 23 I .600E-03 Floor

'1.00 I

Waterhorne 2 .OOOE+00 Vents

10.00

Condensate Drainage 1

!0.00 iSedimsent 25 O.OOOE+00 Floor

Structures-Break I

ool0 JAdheres

...-------------- -

1.00

26 4.O0OE-04 Structures-Break .4- * 1.00

Waterborne 27 0.000E+00 Vents

I0.00

Condensate Drainage I __________________... ------------

10.00- 1 Sedirnent

Structures-Other

0.04

28 O.OOOE+00 Floor

IAdheres 1.00

29 1.600E-03 Structures-Other 4- I 1.00

Canvassed 30 4.f0-0f1 Structulre/Floor i __ ! __ i 0.40 Total I .OOOF44s

NUREG/CR-6369 A-14
Appendix A

DEBRIS TRANSPORT RESULTS I

Plant Design:

Estimate:

Break:

ECCS:

TREE QUANTWICi

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

All Zone-of-Influence

FINAL DISTRIBUTI

MARK I

CENTRAL ESTM _ IRUS INSULATION

MSL BREAK

ECCS THROTTE

.NO SPRAYS

a ION

Vetnlsue lo Structures Structures Structures Transpor t

Above Break Other Fraction

1. 144E-0 1 2.200E-03 3.212E-03 8.712E-03 2.178E-02 6.970E-02 0.5200

O.OOOE+00 0 O.OOOE+00 0 5.1001E-02 2.890E-01 0.0000

3.600E-02 4.OOOE-04 1.600E-03 0 4.OOOE-04 1.600E-03 0.9000

3.600E-02 4. OOOE-04 1.600E-03 0 5.140E-02 2.906E-01 0.0947

1.504E-01 2,600E-03 4.812E-03 8.712E-03 7.318E-02 3.603E-01 0.2507

. 0.1504

O NS (Horizontal)

Vents Enclosures Floor Structures Structures Struct

_ Above Break Other

52.00% 1.00% 1.46% 3.96% 9.90% 31.68

0.00% 0% 0.00% 0% 15.00% 85.00%

90.00% 1.00% 4.00% 0% 1.00% 4.00%

9.47% 0.11% 0.42% 0% 13.53% 76.47

25.07% 0.43% 0.80% 1.45% 12.20% 60.05

. BBUTIONS (Vertical)

Vents Enclosures Floor Above Brea Otr

Above Break Ote

76.06% 84.62% 66.75% 100.00% 29.76% 19.34

0.00% 0% 0.00% 0% 69.69% 80.21

23.94% 15.38% 33.25% 0% 0.55% 0.44%

23.94% 15.38% 33.25% 0% 70.24% 80.66

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

RELATIVE CONTI

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

Debris Transport Fractions

1.000

0

U

U0.750

0.500

0.250

-_

-

_

_

_

Small Debns

0.000 l __ l P l l

Large Above Large Below All Large Debris

Gratings Grabings

All Debris All Zone-ofInfluence

A-1 5 NUREG/CR-6369
Appendix A

LOCA Type Debris Classficat|o DistribudonAfter Erosion and Wasbdown Drywell Floor Pool Path Fraction Flnal Locadon II 

Advected 

Blowdown to Vents

IIINO. I

I 

1.144E-t1

_ I_ _

Vents

MARKI

CENTRAL ESTIMATE

MSL BREAK

ECCS THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

Small Pieces

10.22

0.52

Eaclosures 2 2.200E-03 I Enclosures

0.01

Waterborne 3 0.000E+00 Vents - ----- -. I

iO.00

Dryvell Floor

0.01 ISediment 4 2.200E-03 Floor

Waterbome 5 8.800E-07 Vents

i0.01

ISediment 6 8.712E-05 Floor

Condensate Drainage

0.01

Structures-Above

0.04 Adheres

0.99

7 8.7122E-03 Structures-Above

0.99 t 4. I.

Waterbome 8 1. 100E-04 Vents

0.01

Sprays/Condensate

0.50 Sediment

Structures-Break 0.99

0.10 Adheres

_ _ 9 1 .089E-02 Floor

10 I. 100E-02 Structures-Break t 10.50

Waterborne 11 3.520E-04 Vents

0.01

Sprays/Condensate

0.50 Sediment

Structures-Other 0.99

0.32 Aheres

_ 12 3.485E-02 Floor

13 3.520E-02 Structures-Otber w.Jw

Structures-Brealk

0.15

Large-Above

0.34

iStructmes-0ther

0.85

0.50

Waterbome 14 5.1 OOE-04 Vents

11.00

Sprays/Condensate

0.01 Sediment 15 0.000E+00 Floor 0.00--------

Adheres 16 5.049E-02 Structures-Break

0.99

Waterbome 17 2.890E-03 Vents

1.00

Sprays/Condensate

0.01 Sediment 18 0.000E+00 Floor

0.00

Adheres 1 9 2.861E-01 Structures-Other

VISL Break

1.00

0.99

Advected to Vent 20 3.600E-02 Vents

Enclosures } 21 4.OOOE-04 Enclosures

Large-Below

0.04

Canvassed

0.01

Waterborne 22 0.OOOE+00 Vents

10.00

Drywell Floor _ , _ {

0.04 ISedisucut

1.00

Waterbor

Sprays/Condensate i

0.01 - Sediment

Structures-Break 1.00

0.01 Adheres

0.99

23 I.600E-03 Floor

me 24 0.000E+00 Vents

25 4.000E-06 Floor

26 3.960E-04 Structures-Break .4 4 -4

Watesbome 27 0.000E+00 Vents

'0.00

Sprays/Condensate I

0.01 LSediment

Structures-Other 1.00

0.04 Adheres

_ 28 1.600E-05 Floor

29 I.584E-03 Structures-Other

0.99 4 -4

30 4.000C-O Structures/Floor

( .4 Tntal l .00F+fY

NUREG/CR-6369 A-16
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK I

Estimate: CENTRALESFIBROUS INSULATION

Break: MISL BREAK

ECCS: ECCS THROTTLE

Sprayvs: SPRAYS OPERATED

TREE QUAINTIBCTION

Structures Structures Structures

Debris Classification Vents Enclosures Floor Above Break Other Fraction

Small Pieces 1.149E-01 2.200E-03 4.803E-02 38.712E03 1.10lE-02 3.520E-02 0.5221

Large Pieces-Above 3.400E-03 0 O.OOOE+00 0 5.049E-02 2.861E-01 0.0100

Large Pieces-Below 3.600 .E-04 1.620E-03 0 3.960E-04 1.584E-03 0.9000

All Large Pieces 3.940E-02 4.11%E-04 1.620E-03 0 5.089E-02 2.877E-01 0.1037

All Debris 1.543E-01 2.600E-03 4.965E-02 8.712E-03 6.189E-02 3.229E-01 0.2571

All Zone-of-Influence 0.1543

RENLADITRIVECOTRTIONNS((Verotal)

Debris Classification Vents Enclosures Floor Above Break cter

Small Pieces 52.21% 1.006% .% 3.96% 5.00% 100%

Large Pieces-Above 1.00% 0% 0.00% 0% 14.85%

Large Pieces-Below 90.00% 1.00%_ 4.05% 0% 0.99%

Al Large Pieces 10.37% 0.11% 0.43% 0% 13.39%

All Debris 25.71% 0.43°A 8.27% 14% 1.1

RELATIVE CONTRIBUTIONS (Vertical

es or Structures Structures DersCasfcain Vns Eclsrs For Above Break Ote

Small Pieces 74.46% 84.62% 96.74% 100.00% 17.77% 1.0

Large Pieces-Above 2.20% 0% 0.00% 0% 81.59% 886

Large Pieces-Below 23.34% 115.38% 13.26% 0% 0.64% 104

AR Large Pieces + 25.54% 15.38% 13.26% 0% 82.23%

| Debris Transport Fractions

1.000

0.750

0

Z 0.500

0.250

0.000

Small Debris Large Above Large Below All Large Debris All Debris All Zone-ofGratings Gratings Influence

A-1 7 A-17 NUREG/CR-6369
Appendix A

LOCA Type Debris Classlflcatlo Distribution After Erosion and Washdown Drywell Floor Pool | N ! Fraction Final Location

IBlowdown IINo.I

Advected to Vents I 1.144E-41 Vents

MARK I

CENTRAL ESTIMATE

MSL BREAK

NOT THROTTLED

NO SPRAYS

FIBROUS INSULATION

SnaUll Pieces

0.22

Large-Above

0.34

i Break

1.00

Large-Below

0.04

0.52_

_ r 2 2.200E-03 Enclosures

0.01

Waterborne 3 2.200E-03 Vents

100

DtyweU Floor

.01 Sediment 4 0.000E+00 Floor

0.00

Waterbome 5 8.80E-05 Vents

Condensate Drainage |

0.01 Sediment 6 0.OOOE+00 Floor

Stctures-Above -

5; 7 8.712E-03 Structures-Above

0.99

Waterbome 8 2.200E-02 Vents

1.00

Recirulation iFiow .

00 Sedient 9 0.000E+00 Floor

tutrsBreak * 0.00_ ___ _

0.10 0Adheres o 0.OOOE+00 Structures-Break

0.00__

Waterbone 1 1 7.040E-04 Vents

1.00

Condensate Drainage FO

0.01 'Sedument 12 0.O0OE+00 Floor I----------

Structures-0ther 0.00

0.32 Adheres 13 6.970E-02 Structures-Other

0.99

Waterborae 14 4.080E-03 Vents

1.00

Recirculations Flow

0.08 Sediment 15 0.000E+00 Floor

Structures-Break 0.00

0.15 Adheres 16 4.692E-02 Structures-Break

0.92W

__________ 17 0.OO0E+00 Venos

Condensate Drainage

10.0o -jSediment 18 0.000E+00 Floor

[S=Wctres-Other |9 ---------

O. 85 |Adheres 19 2. 890E401 Stru~ctures-Other

Advected to Vent 20 3.600Ei02 Venbs

0.90_ .

Enclosures 21 4.000E404 Enclosures

0.01

Waterbome 22 I .440E-03 Vents

Drywell _, _ _ _ 

Floor 10.90 _

.. 3.04 I Sediment 23 I .600E-04 Floor

0.10

Waterbome 24 2.OOOE-04 Vents

1.00

iSediment..t 25 0.OOOE+00 Floor

Recirculation Flow

0.50

Structures-Break

0.01 Adheres

0.00

26 2.OOOE-04 Structures-Break _ _ _ . _

0.50

Waterbome 27 0.OOOE+00 Vents

I'1.00

Condensate Drainage - i0.00 Sedimnt

Structures-Other 0.00

0.04 Adheres

t . 28 5 0.000E+00 Floor

29 I .600E-03 Structures-Other _ . _ _

1.00

Canvassed 30 4.OOCE41 Structues/Floer S - - S

0.40 ThNa 1000E+00n

NUREG/CR-6369 A-1 8
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK I

Estimate: CENTRALLESTIMARFSBROUS INSULATION

Break: _ _

ECCS: NOT THROTTED

Sprays: NO SPRAYS

TREE QUANTIMFCATION

.eri Clsiicto Vet.nlsue lo Structures Structures Structures Transport Debris Classification Vents Enclosure Floor Aoe Bek Ohr Fato

Above Break Other Fraction_

Snall Pieces 1.394E-01 2.200E-03 0.OOOE+00 8.712E-03 O.OOOE+00 6.970E-02 0.6336

Large Pieces-Above 4.080E-03 0 O.OOOE+00 0 4.692E-02 2.890E-01 0.0120

Large Pieces-Below 3.764E-02 4.OOOE-04 I 0 2.OOOE-04 1.600E-03 __ - -, .-

Al Large Pieces 4.172E-02 4.000E-04 I

All Debris 1.811E-01 2.600E-03 I

All Zone-of-Influence

FINAL DISTRIBUTIONS (Horizontal) _ _ _ _ _ _ _ _ _ -_ .__ 

j4.712E-02 2.906E-01 i 0.1098

2 A '71T2Rn2 3 hOE-01 0.3019

Debris Classification Vents Enclosures Floor Structures Itructures

Above Break

tructures

Other

Small Pieces 63.36% 1.00% 0.00% 3.96% 0.00% 31.68%

Large Pieces-Above 1.20% 0% 0.00% 0% 13.80% 85.00%

Large Pieces-Below 94.10% 1.00% 0.40% 0% 0.50% 4.00%

Al Large Pieces 10.98% 0.11% 0.04% 0% 12.40% 76.47%

All Debris 30.19% 0.43% 0.03% 1.45% 7.85% 60.05%

REIATIVE CONTRIBUTIONS (Vertical)

- ~~Structuresi Structures Sircue

Debris Classification Vents Enclosures Floor Above Break Other

Snall Pieces 76.96% 84.62% 0.00% 100.00% 0.00% 19.34%

Large Pieces-Above 2.25% 0% 0.00% 0% 99.58% 80.21%

Large Pieces-Below 20.78% 15.38% 100.00% 0% 0.42% 1 0.44%

All T -. Pir ... 23.0/4 15.38%R0/ 100.0o% 0% IMM00.0 8 ZU.I n nr t.... ; IL ._ - I . . -. -

Debris Transport Fractions

1.000

0.750

a

0

CU

IL

0.5004-

0.250 _-

0.000 I _ _S

Small Debris Large Above Large Below All Large Debris

Gralings Gratngs

All Debris All Zone-ofInfluence

A-1 9 NUREG/CR-6369
Appendix A

LOCA Ty Debris 'Dbi 

ClasBlowdo 

lailai jDistribution After w O IPath Eroon and Del oor Pool N. Fratlon | Fial Locatlon

Advected r Ve n ------ - - . -..- I I.. ,^.. MARKI

CENTRAL ESTIMATE

MSL BREAK

NOT TRROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

v enu

0.52 7

Enclosures 2.200E-03 Enclosures A Il t

Waterb'ome 3 2.200E-03 Venh 3 9900F.A1 'I.-.. I.-.. - F. -. ... FDrywell Floor

I.w

l .^. 2.01 SfSediment 4 0.wwOE+w0 Floor

Waterbome 5 8.800E-05 Vents

1600

t

1 t ....... 6 j 0.(ooE+oo Floor

Condensate Drainage

0.01

3tructures-Above

).04 Adheres Small Pieces

10.22

0.00

7 o^.71213-03 Structures-Above 8.712E-03 Stnhctures-Ahove rr1 4 v.yy

Waterborne 8 2.200w2M VenbA

1.00 Recirculation Flow

1.00 ISedt

Structures-Break I I 0.00

0.10 I Adheres

...*I.--- 9 0.ww0E+0w Floor

10 0 0^F^,r CHALAÆA_ rAb ,- ... - -...- - -- - - ------------- n .v w-----ea--reas

v.w

Waterborne II 3.520E402 Venb.

1.00

Sprays/Condensate

10.50 i Sedunen.t

_____0.00

0.32 - JAdhere

t_ = 12 I-------E+0---loo

13 3.520E42 StrubvneVlther

Structue*Break

0.15

lare^Above

0.34

1Struetures Other

0.85

0.50

Waterbome 14 4.080E-03 Vents

1.00

Recirculation Flow

0.08 Sediment 15 0.wwOE+00 Floor

_A dheres 16 4.692E-02 Structues-Break

0.92

Waterbome 17 2.890E-03 Vents

1.00

Sprays/Condensate

0.01 Sedinment 18 0.O0OE+00 Floor

Adheres 19 2.861E-01 Structures-Other MSL Break

1.00 O.^99

Advected to Vent 20 ( I.600E-02 V.-h

D.90

Enclosures 21 4. E-04 Enclosures

Large-Below

0.04 I .u1

Watedjorne 22 I1.440E-v3 Veftw I--- I I I

Drywell Floor

o A j j

0.04 lent 23 1.60OE-04 Floo

1.00

Recircuiation Flow

0.50 Sediment

Structures-Break 0.00

0.01 Adheres

I . _ _-. . inr

le 24 2.000E-04 Vents

25 0.000E+00 Floor .___________

nI 26 2.000EP-04 Q-~leenl -C- ... - I 4 JU SE I

U.50

WaterFborne 27 1.600E-OS I Venbt

1.00

Sprays/Condensate

0.01 ,Sediment

Structures-Other 0.00

0.04 Adheres

t 28 I 0.000E1+00 Floor

29 I .584-03 qf-rhcturech-r I -- I - . . Ubyy

Canvassed 3n I A .II AlO~ xm ¢m^>. I ,A, iLA, JV .wR~l -1-Jue~~o

11 -1 - . I - ----

V.TE.~t~F Iota I . .vOFO A _ I _ _ _ 

NUREG/CR-6369

A-20
Appendix A

I

DEBRIS TRANSPORT RESULTS I

Plant Design:

Estimate:

Break:

ECCS:

SpTrEs:

TREE QUANTIF14

Debris Classificatio

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces v

All Debris

All Zone-of-Influence

_ MARK I, A

NISL BREAK

_NOT THROTTE

_ISPRAYS OEAE

CATION

_ Vet-nlsue lo Structures Structures Structures Transport Enclosures In Floor Above Break Other Fraction

1_ .739E-01 2.200E-03 0.000E+00 8.712E-03 O.OOOE+00 3.520E-02 0.7904

_ 6.970E-03 0 O.OOOE+00 0 4.692E-02 2.861E-01 0.0205

3.766E-02 4.OOOE-04 1.600E-04 0 2.OOOE-04 1.584E-03 0.9414

24.463E-02 4.5%E-04 1.600E-04 0 4.712E-02 2.877E-01 0.1174

2.1851-01 2.600E-03 1.600E-04 8.712E-03 4.712E-02 3.229E-01 03642

% 00.2185

TIONS (Horizontal)

an Vents Enclosures Floor Abv Break Otheru

79.04% 1.00% 0.00% 3.96% 0.00% 10.0%

2.05% 0% 0.00% 0% 13.80% 88.1%

_ 94.14% 1.00% 0.40% 0% 0.50% 3.9%

_ 11.74% 0.11% 0.04% 0% 12.40% 751

36.42% 0.43% _-82/ 0.03% 1.45% 7.85% 

TIUTIONS (Vertical)

_n Vns Ecoue lo Structures StructuresStu

on VnsIcou lo Above Break Ote

_ 79.58% 84.62% 10.00% 100.00% 0.00% 109

3.19% 013% 0.00% 0% 99.58% 89.1

17.23%/ 1538 100.00%/ 0% 0.42% 04

_ 04% 15.38 100.0% 0 100.00% 8.

FTNAL DISTRIBU

Debris Classificatic

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

RELATIVE CON

Debris Classificatfi

of-JIa.L ; ±.A...S 0111 I -11.

Large Pieces-Above

Large Pieces-Below

All Larce Pieces , _

Debris Transport Fractions

1.000

0.750 _-

0

U.

0.500 +_

0.250 1-

Small Debris

l _ l

0.000 l

Large Above Large Belowv All Large Debris

Grabngs Gratings

AJI Debris All Zone-ofInfluence

A-21 NUREGICR-6369
Appendix A

A.3.1.2 Recirculation Line Break

This section contains central estimate logic charts for Mark I recirculation line break scenarios.

A-23 NUREG/CR-6369
Appendix A

LOCA Type IDebris Clsiico DBtlbwdown AIe Eroion sad Wasdowa DNwllo o .l Fraction IFinal Location

Advected to Vents KI 

I I 1.012E-01 I___Vents

MARKI

CENTRAL ESTIMATE

RL BREAK

ECCS THROTTLED

NO SPRAYS

FIBROUS INSULATION

Stnall Pieces

10.22

0.46 _

Enclosures 2 2.200E-03 Enclosures

0.01

Waterborne 3 4.400E-02 Ventb

Drywell Floor I1.00

0.20 _ Sedirnent

0.00

Waterbom

4 O.00OF+00 PI- _______... _ v -- _v . w

e 5 4.400E-05 Vents

- 6 0.000E+00 Floor

1.00

Condensate Drainage

0.01 ,Sedirnent

Strftutus-Above 0.00

).02 Adheres

0.99

Waterbom

1.00

Recarculation Flow

1.00 'Sediraent

StucturesBreak 0.00

3.08 I

7 4.356E-03 Structures-Above _ _ _

e 8 1.760E-02 Vents

__________ 9 0.000E+00 Floor

10 0.000E+00 Structures-Break --------------------------------

0.00

Waterbome It 5.060E-04 Vents

1.00

Condensate Drainage

0.01 'Sediment

Structures-lther 0.00

0.23 Adheres

- 12 1 0.000E+00 Floor

13 5.009E-02 Structures-Other

Structures-Break

0.15

Large-Above

0.34

[Strctures-Otber

0.85

0.99

Waterborne 14 4.080E-03 Vents

1.00

Recirculation Flow

0.08 iSediment 15 0.000E+00 Floor

0.00

Adheres 16 4.692E402 Structures-Break

0.92

Waterbome 17 0.000E+00 Vents

'1.00

Condensate Drainage i

0o.00 ISedient 18 0.000E+00 Floor

Adheres 19 2.890E401 Stnctures-Other

RL Break

1.00 Advected to Vent 20 3.600E-02 Vents

0.90

Enclosures 21 4.000E-04 Enclosures r "_AO D..IA...

= Itelow 0 .01

Waterbone 22 1 .440E-03 Vents

10.90

Drywell Floor :. IA

0.04 lSediment 23 | 1.6002-04 Floor

0.10

Waterborne 24 2.0002-04 Vents

1.00

iSedinrent - ---- 25 0.00024-00 Floor

Recirculation Flow

0.50

Sosutures-Break

0.01 Adheres

0.00

26 2.000E-04 Structures-Break _ _ _ 0.50

Watesborne 27 0.OOOE+00 Vents

'1.00

Condensate Drainage 1

.o.0oo Sedirnent

Structures-Other * 0.00

0.04 [Adheres

_____. 28 0.000E+001 Floor

29 I ..600E-03 Structures-Other __ _ _

1.00

Canvassed 30 4.000E-01 Structures/Floor

0.40 Totia 1 i nn=E4f

NUREG/CR-6369 A-24
Appendix A

Plant Design: MIARK I

Estimate: CENTRAL ESTIAFIBROUS INSULATION

Break:RBEA

ECCS:ECSHO

Sprays OSRY

TREE QUANTIFICATION

Derilasiito VetsEnlsuesFlo Structures Structures Structure Transport

DersCasIcto et EnlsrI lo Above Break Othere Fraction

Sml1iee .634E-01 2.200E3-03 0.OOOE+00 4.356E-03 0.000E+00 5.009E-02 0.7425

Large Pieces-Above 4.080E-03 I 0 0.OOOE3+00 0 1 4. !.890E-0 1 0.0120

Large Pieces-Below 3.764E-1 4.OOOE-04

A VV~fAr_(A

.04

All Large Pieces 4

0

0

I ' 1.600E-03 0.9410

-2.906E-01l 0.1098

'A AMP-A 0.3418

0.2051

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification Vents Enclosures Floor Structures Structures Structures

Aboe I Break I Other

Small Pieces 74.25% 1.00% I 0.00% 1.98% j 0.0%j

Large Pieces-Above 1.20% 0% 0.00% AO/ 13.80% 1 85.00%

Large Pieces-B-elow 194.10% 11.00% 10.40% 0% j0

All Large Pieces 10.98% 0.11% 0.0.4% 0%

All Debris 34. 18% 0.43% 0_71%/

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Structures

Above

,,rructures IStructures

Break IOther

Lmarge Pieces-Abve 9.99% 046% 0.00% 10.0% 99.58% 84.83%

Smalle Pieces-Ao 7 1996% 846% 00% 10.00% 0% 9.00% 14.70%

Large Pieces-Below 18.35% 15.38% 100.00% j 0% j0.42% 0.47%

All Large Pieces 20.34% 15.38% J100.00% j 0% j10-0.00% J85.30%

Debris Transport Fractions

1.000

0.750 -1----

C0

(a

U0.500 +---

0.250 +-1--

0.000 -

Small Debris

i i I I

Large Above Large Below All Large Debris ~AJ[ Debris

Gratfngs Gratings

Al Zone-ofInfluence

A-25 A-25 NUREG/CR-6369
Appendix A

LOCA Type LOC TpeDebisClssiicdoDistribution Debri Classif After Erosion and Washdow |cYt|oNo.P Drywell Mloor Pool Pah ! Fraction !I Final Location II Blowdown I TNO.

Anvectns to vents I I.012E-01 Vents

MARKI

CENTRAL ESTIMATE

RL BREAK

ECCS THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

Small Pieces

10.22

0.46 E

Enclosures 2 42 2.200E-03 I Enclosures

0.01

Waterborne 3 400E-02 Vents ..-- II

Drywell Floor I1.00

0.20 iSediment 4 0.000E+00 Flmr

0.00 Waterboent 6 4 .400E405 Yenb

,Sedimnent ~ 6 0.000E+Do Floo~r

Condensate Drainage

0.01

Structures-Above

0.02 cAdheres

0.uO

7 1 4.356E-03 Structures-Above + -4 -4-

0.99

Waterborne 8 1.760E-02 Vents

1.00

Recirculaion Flow I

1.00 Sediment

StractureaBreak_ 0.00

0.08 iAdheres

9 0.OOOE+00 Floor ,__________

10 0.000E+00 Stuctures-Break - A------_- _ -_-_-_-_-_-_-_-_

0.00

Watertme 11 2.530E-02 Vents

1.00

Sprays/Condensate

0.50 "Sedinent

Structures{-ther 0.00

0.23 Adheres

____ 12 0.000E+00 Floor

13 2.530E-02 Structures-Other

Structure+-Break

0.15

Large-Above

0.34

Strixtures-0ter

0.85

0.50

Waterborne 14 4.080E-03 Vents

1.00

Recirculation Flow

0.08 Sediment 15 0.OOOE+00 Floor

0.00

Adheres 16 4.692E-02 Structures-Break

0.92

Waterborne 17 2.890E-03 Vents

1.00

Sprays/Condensate

0.01 ,Sediment 18 0.000E+00 Floor

Adheres 19 2.861E-01 Structures-Other

R L Break

1.00

0.99

Advected to Vent 20 3.600E-02 Vents

2.90

Enclosures 21 4.000E-04 Enclosures

Large-Below

0.04 Wateftome 22 1 .440E-03 Vents

10.90

Drywell Floor .~I _

0.04 Sedinment 23 I .600E-04 Floor

0.10

Waterbome 24 2.000E-04 Vents

1.00

_ Sediment 25 O.OOOE+00 Floor

Recirculation Flow

0.50

Structures-Break

0.01 Adheres

0.00

26 2.000E-04 Structures-Break _ __ _

0.50

Waterbome 27 1.600E-05 Vents

1.00

Sprays/Condensate

0.01 ISediment

Structures-Other 0.00

0.04 Adheres

L ___ .1___ 28 O.OOOE+00 Floor

29 I .584E-03 Structures-Other

0.99 F . ._______

Canvassed 30 4.000E-01 Structures/Floor F F 0.40 I OoOl+pn0

NUREG/CR-6369 A-26
Appendix A

DEBRIS TRANSPORT RESULTS I

Plant Design:

Estimate:

Break:

ECCS:

TREE QUANTLFICM

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

All Zone-of-Influence

FINAL DISTRIBUTF

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

RELATIVE CONTF

Debris Classification

Smnall Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

MIARK I

RL BREAKi

ECCS OLE

SPRAYS OPERATED|

TION

. Vents Enclosures Floor Structures Structures Structures Transport V Above Break Other Fraction

1.881E-01 2.200E-03 O.OOOE+00 4.356E-03 0.OOOE+00 2.530E-02 0.8552

6.970E-03 0 O.OOOE+00 0 4.692E-02 2.861E-01 0.0205

3.766E-02 4.OOOE-04 1.600E-04 0 2.000E-04 1.584E-03 0.9414

_ 4.463E-02 4.OOOE-04 1.600E-04 0 4.712E-02 2.877E-01 0.1174

_2.328E-01 2.60013-03 1.600E-04 4.356E-03 4.712E-02 3.130E-01 0.3880

DNS (Horizon

Vents Enclosures Floor Structures Structures Structur

Above Break Other

85.52% 1.00% 0.00% 1.98% 0.00% 11.50%

2.05% 0% 0.00% 0% 13.80% 84.15%

94.14% 1.00% 0.40% 0% 0.50% 3.96%

11.74% 0.11% 0.04% 0% 12.40% 75.71%

38.80% 0.43% 0.03% 0.73% 7.85% 52.17%

[BUTIONS (Vertca

Vents Enclosures Floor Srove Brea Otr Above Break Ote

80.83% 84.62% 0.00% 100.00% 0.00% 8.08%

2.99% 0% 0.00% 0% 99.58% 91.41%

16.18% 15.38% 100.00% 0% 0.42% 0.51%

19.17% 15.38% 100.00% 0% 100.00% 91.92%

Debris Transport Fractions

1.000 -

0.750 -

U 0.500 -

0.250 -

0.000 - l _ l l l_ l

Small Debris Large Above Large Below All Large Debris

Gratings Gratings

All Debris All Zone-ofInfluence

A-27 ANUREG/CR-6369
Appendix A

LOCA TypeB|Debrls Classiowcado Blod|on Erosion and Wasbdown Drywell Floor Pool Path Final Locadon A t o V e n ts I I N o . I Fn Advected to vensI LE I

MARK I I ...- . a

Enclosures I

CENTRAL ESTIMATE

RL BREAK

NOT THROTTLED

NO SPRAYS

FIBROUS INSULATION

n I I I I V.V

Waterbome 3 4

2.200E-03

4.40uE402

Vents

Enclosures

Vents I, -1 ..OJE0

Drywell Floor gI.W

I -A I-u Sedint

6.---_-_----------

0.00

4 0.000E+00 Floor

WateTborne

1.00

Condensate Drainage

0.01 ,Sediment

Structures-Above 0.----------------

0.02 Adheres

5 4.400E-05 Vents

6

7

Small Pieces

r0.22

0.000E+00

iA- .

7 4 lgFrn u. u

Waterbore 8 I1,760EOM 8 I. _ . ._ 1.00

Recirculation Flow

1.00 iedi nt Break I.d-et--s - -_ I 0.00

0.08 1 Adher

Floor

Structures-Abov.

Vents

Floor

Structures-Break

Vents

9

10

0.OOOE+00

0.000E+00

5.060F.-04

A- AA --- ---- ------------ ________- L v

O.wO

Wateiborne 11

11.00 Condensate Drainage 1

0.01 IS t Sv^UWWt0d~er I o0.00

0.23 -Adheres

.t__ ___ _ T1 12 0.w0E+00 T Floor

13 I GA< r fl 1, ;.vWZ

O.YY

Waterborne 14 1377E-02

Structures-Breakc ----------

0.0

I ...

0.15 Adheres

0.73

1.000

11arge-Above ICondAnsate dtoinag V

10.0: ow Sedmn

I rctue s. the 1 ----------- ----- |0.85 _Adberes

W Aavected to Vent

Structures-Other

Vents

Floor

Structures-Break

1 5 . _1 II1A

O.00E+00

It 7^,1P

I

e

i ; 2 1flA

1 7 1 .0001+00 ._ _

18

19

0.000E+00

2.890E-0I

t -r^

RL Break

1.00

19.

Vents

EOOT

Structures-Other

Vents

Enclosures

Vents

an

I GA L-~.-L

Enclosures a I I _ A_, gelow

0.04

I

n..vi

Waterbome 22 I.440E-03

Drywell Floor

0.04

10.90

0 Sediment

0.10

23 1.600E-04 Floor

Watesbore 24 2 .OOOn4 I1.00

Recirculation Flow

0.50 ISediment

Strutures-Break -------- 0.00

0.01 Adheres

-Foo

______ 25 O.OOOE+00 Floor

26 2.OOOE-04 Structures-Break n C A 4 - u.;u

Waterbome 27 n O (mp44) V___

.

I- --------------- . _ 7_ . n r 4 s_ I Iv -e

11.00

Condensate Drainage I

10.00 -- Sedime, Structures-Other ° 00 

0.04 |Adheres

28

29

0.OOOE+00 Floor

I _nnn- K^ - APA._ LAA 1 G A. z ~ ~ h r u r u r e -c i s ne r

Canvassed I bW

L [30 4.0 OOE-01I Stractures/Floor r

Total I I .000F+00 I

NUREG/CR-6369 A-28
Appendix A

DEBRIS TRANSPORT RESULTS -~1

Plant Design:

Estimate:

Break:

ECCS:

TREE QUANTIFIC

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

All Zone-of-Influence

NMARK I

CENTRAL ESTures FloorA ABa O t

_RL BREAK

_ THROTTLED -NOT 0

.7NO SPRAYS 0

AIO

Vents Enclosures Floor Structures Structures Structures Transport

Above Break Other Fraction

1.634E-01 2.2+0 0.0 0 4.356E-03 0. +00 5.009E-02 0.7425

1.377E-02 0 0.OO1+00 0 3.723E-02 2.890E-01 0.0405

93764E-02 4.%OOE-04 1. 4 0 0.0% .600E-03 0.9410

5.1413E-02 4.OOE-04 1.600E-04 0 3.743E-02 2.90687 01 0.1353

_2.148E-01 2.600E-03 1.600E-0.4 4.35613-03 3.743E-02 3.407E-01 0.3579

% 00.2148

IONS (Horizontal)

_ E F Structures Structures Struc

l Vents Enclosures Floor Abe Bra Otr

Above Break Ote

74.25% 1.00% 0.00% 1.98% 0.00% 14.70%

4.05% 0% 0.00% 0% 10.95% 84.83%

_94.10% 1 .00% 0.40% 0% 0.50% 400

13.53% 0.11% 0.04% 0% 9.85% 0.47%

35.79% 0.43% 0.03% 0.73% 6.24% 56.78%

RIBUTIONS (Vrticall)

Vent Ecosues Foor Structures Structures Structures _ et nlsrs For Above Break Other

76.06% 84.62% 7 0.00% 100.00% 0 .00% 14.70

_ 6.41% 0% 0.00% 0% 99.47% 84.83

17.53% 15.38%/ 100.00%/ 0%/ 0.53% 0.47

_ 23.94% 115.38% 100.00% 0% 100.00% 85.30%

FINAL DISTRIBUTI

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

RELATIVE CONTI

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

Debris Transport Fractions

1.000

0.750 IC

0

U to .50

0.250 _--

0.000 l I_ I i

Small Debris Al Zone-ofInfluenceLarge Above

Gratings

Large Below All Large Debris

Gratings

All Debris

A-29 A-29 NUREG/CR-6369
Appendix A

LOCAType DebrisC ficto Distribution After Erosion and Washdown Drywel Floor Pool | I Fraction Foaal Location

II Blowdown IINo.I

Advected to Vents I 1.012E-01 Vents

MARK I

CENTRAL ESTIMATE

RI BREAK

NOT THROTFLED

SPRAYS OPERATED

FIBROUS INSULATION

Small Pieces

10.22

0.46

Enclosures 2 2.200E-03 I Enclosures

0.01

Waterbome 3 4AOOE-02 Vents * + 4

Drywell Floor I1.00

_ _ t ,, 0.20 iSedirent 4 1 0.000E+00 Floor

0.00

Waterbome 5 4.400E-05 Vents

1.00

L1 ........ 6 0.OOOE+00 Floor

Condensate Drainage

0.01

Struchre-Above

0.02 Adheres

0.00

7 4.356E-03 _

Structures-Above I 0.99

Waterborne 8 1.760E-02 Vents

Redirculation Flow |I~

0.00I

Waterborn

.Sprays/Condensate I.0

Ftutrste 0.00 0.23 -- Adhere

1.00- 0t0E+00 Floor

10 0.000E+00 Stuctures-Break _ _ - - - - - - - -

11 2.530E-02 Vents

..._____ __ 12 0.000E+00 _ _ Floor

13 2.5304-02 Structures-0ther

Structures-Break

0.15

Large-Above

0.34

lStructures Ohe

0.85

Advecteo to Vent

0.50

Waterborne 14 1.377E02 Vents

1.00

Recirculation Flow

0.27 Sediment 15 0.000E+00 Floor

0.00

_Adheres 16 3.723E-02 Structures-Break

0.73

Waterborne 17 2.890E-03 Vents

1.00

SpraystCondensate

0.01 Sediment I8 0.000E+00 Floor

0.00

_Adheres 19 2.861E-01 Structures-Other

RL Break

1.00

0.99

20 3.600E-02 Vents

0.90 t

Enclosures 21 14.OO00-04 I Enclosures

Large-Below

0.04

0.01

Waterborne 22 1 .440E-03 Vents

Drywell Floor 10.90 . c

0.04 Sedinent 23 | 1.600E-04 Floor

0.101

Waterboame 24 2.000E-04 Vents

1.00

iSediment 

..._ 25 0.0004+000 Floor __ __ __ __ _ ____ _ _ _

Recirculation Flow

0.50

Structues-Break

0.01 Adheres

0.00

26 2.000E-04 Stru-ctures-Break 4 + 0.50

Waterbome 27 1.600E-05 Vents

1.00

Sprays/Condensate

0.01 Sediment

Structures-Other 0.00

0.04 Adheres

- 28 1 0.0000400 t Floor

29 1 .584E-03 Structures-Other 4 4. 0.99

Canvassed 30 4.000E-01 Structurev/Floor 4 ._ 04 Af T>7>1 I or +n

NUREG/CR-6369 A-30
Appendix A

DEBRIS TRANSPORT RESULTS I

Plant Design:

Estimate:

Break:

ECCS:

TREE QUANTIFICA

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

All Zone-of-Influence

FINAL DISTRIBUTI'

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

MARK I

RL BREAK|

NOTTHO LE>

.SPRAYS OPRAE

lMION

Vet.nlsue lo Structures Structures Structures Transport

Above Break Other Fraction

1.881E-01 2.200E-03 0.000E3+00 4.356E-03 0.000E+00 2.530E-02 0.8552

1.666E-02 0 0.OOOE+00 0 3.723E-02 2.861E-01 0.0490

3.766E-02 4.OOOE-04 1.600E-04 0 2.OOOE-04 1.584E-03 0.9414

.5.432E-02 4.OOOE-04 1.600E-04 0 3.74313-02 2.877E-01 0.1429

2.425E-01 2.600E-03 1.60013-04 4.35611-03 3.743E-02 3.130E-01 0.4041

0.2425

Vents Enclosures Floor Structures Structures Structur

Above Break Other

85.52% 1.00% 0.00% 1.98% 0.00% 11.50%

4.90% 0% 0.00% 0% 10.95% 84.15%

94.14% 1.00% 0.40% 0% 0.50% 3.96%

14.29% 0.11% 0.04% 0% 9.85% 75.71%

40.41% 0.43% 0.03% 0.73% 6.24% 52.17%

RIBUTIONS (Vertical)

_ - Structures Structures Structures

Vents Enclosures Floor Above Break Other

77.60% 84.62% 0.00% 100.00% 0.00% 8.08

6.87% 0% 0.00% 0% 99.47% 91.41

15.53% 15.38% 100.00% 0% 0.53% _0.51

22.40% 15.38% 100.00% 0% 100.00% 91.92%

RELATIVE CONTI

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces -

Debris Transport Fractions

1.000

0.750 er-0

t;0.500

U0.250 _--

0.000 - I Or_ I I _

Small Debris Large Above

Gratngs

Large Below All Large Debris

Gratings

All Debris All Zone-ofInfluence

A-31 NUREGICR-6369
Appendix A

A.3.2 Mark II

This section contains the central estimate logic charts for the Mark II design.

A.3.2.1 Main Steam Line Break

The central estimate logic charts for the main steam line breaks are presented here, then the charts for

the recirculation line breaks are presented in Section A.3.2.2.

A-33 NUREG/CR-6369
Appendix A

LOCA Tlpe |Debris Classificationl Bldon Erosion and Wasbdownl Dryweli Floor Po

Advected to Vents I

MARK 11

CENTRAL ESTIMATE

MSL BREAK

ECCS THROTTLED

NO SPRAYS

FIBROUS INSULATION

OI V;

Enclosures

0.01

Waterbome

Drywell Floor|

0.06 Sednnent

1.00

Waterbome

,_______________

'0.00

Condensate Drainage I

0.01 Sedimt

Structures-Above 1.00

.03 Adheres

0.99

Waterbomne

Condensate Drainage 1700-------

Structures-Break 1.00

0.09 ~ Adhere

Small Pieces

10.ZI

0.99

Waterbome

O00

Condensate Drainage -

0.01 Sedinent

Structures-Other 1.00

0.26 Adheres

0.99

Waterbome

10.00

Condensste Drainage

'0.00 ISediment

Structures-treak I - - -

0.1_

1.00

Wateroome

- ______. -------- Large-Above CodnatMring W

0.4 0.00 -- Sedirnen,

Stutures-Other 1 -1.00 ------- 0.85 Adheres

1.00 Advected to Vent

Pa No. IL Fraction Floal Location

I 1.210E-01 Vents

2 2.200E-03 Enclosures

3 0.000E+00 Vents

4 1 .320E-02 Floor

5 0.OOOE+00 Vents

6 6.600E-05 Floor

7 6.534E-03 Structures-Above

8 0.000E+00 Vents

9 I 980E-04 Floor

0 1.960E-02 Structures-Break

_ i 0.OOOE+00 Vents

512 .720E-04 Floor

1 5.663E-02 Structures-Other

14 0.000E+00 Vents

15 0.000E+00 Floor

_ 16 i5100E-42 Structures-Break

17 0.OOOE+00 Vents

18 0.000E+00 Floor

19 2.890E-01 Structures-Other

20 3.600E-02 Vents

21 4.OOOE-04 Enclosures

22 0.OOOE+00 Vents

.23 1.600E-03 Floor

24 0.000E+00 Venb

25 0.000E+00 Floor

26 4.000E-04 Structures-Break

27 0.000E+00 Vents

28 0.OOOE+00 Floor

29 I.600E-03 Structures-Other

30 4.000E-01 Structures/Floor

aaLF t.OO

MSL Break

1.00

n0an

Large-Below

0.04

Canvassed

0.01

Drywell Floor

Waterbome

r----___

ISedirnent

.__________

U.04

10.00-

Waterbome

Condensate Drainage t

:0.00 - Sediment

Structures-Break t -t_____________

0.01 -lAderes

1100

Water0ooAe

I------- --------

t0.00 ,-Sedi.,n Strutures4Other ------------

0.04 lAdheres

I.vv

I I An

I

NUREG/CR-6369 

A3A-34
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARKII

Estimate: CENTRALE FIBROUS INSULATION

Break: ISL BREAK

ECCS:ECCSTHRO

Sprays NO SPRAYS

TREE QUANTIFICATION

Debris Classification Vents Enclosures Floor Structures Structures Structures Transport

b E Above Break Other Fraction

Small Pieces 1.210E-01 2.200E-03 1.404E-02 6.534E-03 1.960E-02 5.663E-02 0.5500

Large Pieces-Above 0.OOOE+00I 0 0.OOOE+00 0 5. 100E-02 2.890E-01 0.0000 ______ I. I 4 4 v _-

Large Pieces-Below 3 I 4.-OE-04 1.600E-03 0 4.OOOE-04 1.600E-03 0.900 in I. I-'I t

All Large Pieces 3__

1.600E-03

L.564E-02

0 5.140E-02 2.906E-01 I. I 4 I 0.0947

All Debris 6.534E-03 I 7.100E-02 3.472E

All Zone-of-Influence

FINAL DISTRIBUTIONS (Horizontal) Y

Debris Classification Vents Enclosures Floor tructures I Structures Structurn

Above I Break I Other

Smnall Pieces 55.00% 1.00% 6.38% 2.97% 8.91% 25.74%

Large Pieces-Above 0.00% 0% 0.00% 0% 15.00% 85.00%

Large Pieces-Below 90.00% 1.00% 4.00% 0% 1.00% 4.00%

All Large Pieces 9.47% 0.11% 0.42% 0% 13.53% 76.47%

All Debris 26.17% 0.43% 2.61% 1.09% 11.83% 57.87%

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Above Break Other

Small Pieces 77.07% 84.62% 89.77% 100.00% 27.61% 16.31%

Large Pieces-Above 0.00% 0% 0.00% 0% 71.83% 83.23%

Large Pieces-Below 22.93% 15.38% 10.23% 0% 0.56% | 0.46%

All Large Pieces 22.93% 15.38% 10.23% 0% 72.39% | 83.69%

Debris Transport Fractions

1.000

0.750

C

0

4U

UA.

0.500 t0.250 -

0.000 -v- l _ l

Small Debris Large Above Large Below Ad[ Large Debris

Gratings Gratings

All Debns All Zone-ofInfluence

A-35 NUREG/CR-6369
Appendix A

E ro|in _ and W hdown Drywell Floor Poo3 | Fraction Flna Location

I_ _ _ _ _ _ _ _ _ _ _ __I_ . o'

MARK 11

CENTRAL ESTIMATE

MSL BREAK

ECCS THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

. t -71 F. SA_ . 1 I vents 0.55

Enclosures 2 2.0 losures

f) v.-l +%

Waterbome 3 6.600E-03 Venbs Vents -4.

Dry"ell Floor

10.50

0.06 SedirLnen

0.50

WateTborr

4 6.600E-3 Fw-r

Sn~aI Pieces

022

0.00

Strvictures-Abovve 0. 10

0.03 Adheres

0.99

Waterborn

0.90

Sprays/Condensate

0.50 Sediment

St0.tures-Break 0.10

0.09 ]Adheres

7 6.534E-03 St-h-orAbh-v

ne 5 5.940E-05 Vents

6 6.600E-06 Floor

7 6._34E-03

e 8 S.91 OE-03 Venb

:9 9.900E-04 Floor

10 9.900E-03, Rt-vh-Rreak

n _ _ _ _ __cn_ _ _ _ _ ._ I V.JU

Waterborne II 2.574E-02 Venhs

0.90

Spwys/Condensate

0.50 Sedinent

Str0ucte ther .10

0.26 Adheres

-_________ 12 2 asoor

I1' 2) R~nvn7 RYwhl ou,

Sftw ru tuBreak

0.15

lare-Above

0.34

IStrucues-DFther

O.SS

0.50

Waterbome 14 5. 1OO-04 Vents

1.00

Sprays/Condensate

0.01 .Sediment 15 0.000E+O0 Floor

lAdheres 16 5.049E-02 Structures-Break

0.99

WateIbome 17 2.890Ew03 Vents

1.00

Sprays/Condensate

0.01 Sedinct 18 0.000E+00 Floor

Adheres 19 2.861w-01 Structres-Other M[SL Break

1.00 U.YY

Advected to Vent 20 3.60OE402 Venhs

0.90 _ - _ . _ 

Enclosures 21 4.000w-04 Enclosures

Large-Below

0.04

J.jvU

Waterborme 22 O.OOOE+00 Venb. r---A ------- V. V

Dryvell Floor 10.4.0

- :. i

0.04 [ Sediment 23 1.600E-03 Rloor

IC 24 0.000E+00 Vents

25 4.000B-06 Floor

10.00

Sprays/Condensate I

0.01 [Sediment

Stractures-Break 1.00

0.01 Adheres 26 3.960E44-A Sh .. .fi. mRrs _ v

4 -_ i _ .I__ 

Waterbome

a0.00

Sprays/Condensate I

0.01 Sediment

StturesOther 1.00

0.04 Adheres

27 0 AA,00E+0 0 Venhs

28 I .600E-45 Foor

29 1.584E-03 Structures-Other _ _ _ A_ _ _

0.99 Canvassed I v nnn>,. AI- _--.-_---I-C AA__

0.40 C ,u -. uu-u I Orvuerloor v -]otl

NUREG/CR-6369

A-36
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: _ MRK II

Estimate: CENTRALES AFIBROUS INSULATION

Break. SL BREAKI

ECCS: ECCS THRO

SPRAYS OPERATED

TREE QUANTIFICATION

. . Structures Structures Structures Transport

Debris Classification Vents Enclosures Floor Aoe Bek Ohr Fato IIAbove IBreak IOther Fraction

Small Pieces 1.623E-01 2.200E-03 1.046E-02 6.534E-03 9.900E-03 2.860A02 0.7378_

T nrae PiwecAhnve 3400FR03 0 O.OOOE+00 0 5.049E-02 2.861E-01I . - . . - __ __ I E - - - - i

Large Pieces-Below 3.600R-02 4.OOOE-04 1. 0 3.960E-04 1.584E-03 I

.9 9-?-

All Large Pieces 3.940E-02 4.OOOE-04 1 0 15.089E-02 2.877E-01 I . __

2.017E-01 2 F ;-1AI nA h n7Q02- 3 i63E-01 I

FINAL DISTRIBUTIONS (Horizontal) . .

Debris Classification Vents Enclosures Floor Structures Itructures

Above Break

Miructures

Other

I. I-I t I - I 4,50% SRnlil PiecesR 73.78% 1.00% 4.75% 2.97% 4.50% 1

Large Pieces-Above 1.O00% 0% 0.00% j 0% j 14.85% 844. I)15/

Large Pieces-Below 90.00% 1.00% 4.05% 0% 0.99%

9 -I-9 I* 'IAll Large Pieces 10.37% ram 1

l ~ 0.43% ._ .. _ l 0%_ .- _ 13.39%

AR Debris C 33.62%

RELATIVE CONTRIBUTIONS

v, A1o0/

Vertical) I Y -

res

Debris Classification Vents Enclosures Floor Structures Structures

Above Break I Other

Small Pieces 80.47% 84.62% 86.59% 100.00% 16.29% 9.04%

Large Pieces-Above 1.69% 0% 0.00% 0% 83.06% 90.46%

Large Pieces-Below 17.85% 15.38% 13.41% 0% 0.65% 0.50%

All Large Pieces 19.53% 15.38% 13.41% 0% 83.71% 90.96%

Debris Transport Fractions

1.000

0.750 -

C

0

U;

U0.500 +-

0.250 _-

0.000 -- l {_^_ l l

Srnall Debris Large Above Large Below All Large Debris

Gratings Gratings

All Debris All Zone-ofInfluence

A-37 NUREG/CR-6369
Appendix A

LOCA Type Debris Classificado Diatribudon After |nFrI Fraclation Adveeiowdo E^nNo..a &A - 4.-1 -

MARKICI

CENTRAL ESTIMATE

MSL BREAK

NOT THROTTLED

NO SPRAYS

FIBROUS INSULATION

nvv>;usu w - I I1.210-01 Vent0.55 .. .. , Enclosures ZOOEE o

- uL

Waterbome 3 1320E-02 Vents ___ -4- ________

Drywell Floor |I.00

-I 0.06 iSedinent 4 O.OOE00F4A Eoor ------- _

0.00

Watesbon

.___________ - ----- . .Lw

re 5 6.600E-05 Vents

I---------- 6 O.OOOE+00 Floor

Snal] Pieces

10.22

1.00

Condensate Drainagc

0.01 Sedimevt

StructurmsAbove 0.00

0.03 Adheres

0.99

Waterborn

1.00

Recuulation Flow

1.00 SI

Str0.09 s-Break 0.

0.09 iAdheres

7 6.534E-03 qvvt-re-Abvi

Le 8 1.980E-02 Vents

________ 9 0.OOOE+00 Floor

in n (mrOF+fA R"^nr-- - n- ...-... . I,- u.wO

Watesbone 11 5.720E-C4 Venh

1.00

Condensate Drainage

0.01 Sediment

Strtusres-Other 0.00

0.26 Adheres

-______ 12fO.OOOE+00f Flor

13 5.663E-02 Structuher~t,

StructumBreak

0.15

[zrge-Abwve

D.34

Structvns-ther

0.85

0.99

Waterbome 14 4.080E-03 Vents

1.00

Recirculaton Flow

0.08 Sedirnet 15 O.OOOE+00 Floor

_Adhere 16 4.692E-02 Stnxcnires-Break

0.92

Waterborne 17 O.OOOE+00 Vents

Condensate Drainage j

0.oo 0 - Sediment 18 0.000E+00 Floor

| 10.00

Ahrs19 2.890E-01 Strmctres-Odse MSL Break

1.00 I .U

Advected to Vent 20 3.600P02 Venh

0.90 4

Enclosures 21 )4000E404 Enclosures

arge-Below fl. t

0.04 Waebomne 22 1.600E-03 Vents 4 4

Drylwel Floor I1.00

0.04 'Sediment 23 O.DOOE+00 Floor

Waterbome 24 2 .000E04 Vents

1.00

!Sedi-et .. 25 0.000E+00 Floor

Recirculation Flow

0.50

Stntures-Break

0.01 Adhies

0.00

26 2.000E-04 S tructur-eL rek _ __ ___ _I_ _-_-_ ______ V Vo W

0.50

Watertome 27 0.000E+00 Vents

Condensate Drainage I

10.00 ... Sediet

Strmctu5-Other I 0.00

0.04 IAdheres

__________ 28 O.O0E+00 Floor

29 1.60OE-03 qtnwuh-q-th-r

. ,01.I)

Canvassed 30 4MP-ol d m I or

I - I -- I '. - 1-1

van- T ,. I . A^^ - . - I v. __al M _ __I I__ A .+f0 I

NUREG/CR-6369 A-38
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK II T

Estimate: CENTRAL ESTIMA FIBROUS INSULATION

Break.SL BREAK

ECCS:NOT THROTTLE

Sprays: NO SPRAYS

TREE QUANTIFICATION

. . Structures Structures Structures Transport Debris Classification Vents Enclosures Floor Above Brea Other Fracspon S I Above Break Other Fraction

Sra ics1.546E-01 I2.200E-03 IO.OOOE+00 6.53411-03 IO.OOOE+00 I5.663E-02 0.7029

Large Pieces-Above 4.080E-03 0 O.OOOE+00 0 4.6921E-02 I 2.8901E-01 0.0120 J 4 & I .1

Large Pieces-Below 3.

All Large Pieces 4.

4.OOOE-04

4.OOOE-04

2 6nn0E-03

0.000E+00

0.000E+00

0.OOOE,+00

0 2.OOOE-041I1 .6001E-03 0.9450 . -

0 4.712E-02 I2.906E-01

4.712E-02 3.472E-01

0.1102

t

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification Vents Enclosures Floor tructures I Structures

Above I Break

Structure

Small Pieces 70.29% 1.00% _ 0.00%_ _ 2.97% [ 0.00% I

Large Pieces-Above 1.20% 1 0% 0.00% 0% I13.80%

.74%

Large Pieces-Below 94.50% 1.00% 0.00% 0% 0.50% 4.00%

All Large Pieces 11.02% 0.11% 0.00% 0% 12.40% 76.47%

All Debris 32.75% 0.43% 0.00% 1.09% 7.85% 57.87%

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Above Brea Other Above Break Other

Srmall Pieces 78.69% 84.62% N/A 100.00% 0.00% 16.31%

Large Pieces-Above 2.08% 0% N/A 0% 99.58% 83.23%

Large Pieces-Below 19.23% 15.38% N/A 0%, 0.42% 0.46%

All Large Pieces 21.31% 15.38% N/A 0% 100.00% 83.69%

Debris Transport Fractions

1.000 -

0.750 -

lo

o 0,500

0.250

0.000 - l _ l l

l _ l

All Zone-ofInfluence

Small Debris Large Above Large Below All Large Debris

Gratings Grabngs

All Debris

A-39 A-39 NUREG/CR-6369
Appendix A

LATyeDriCanilaoDstsbibution After PathI

LOA Iebi yp Casifcafol Blowdown IErosion and WashdowuI Drywell Floor PoolNo Fraction F~Inal Location _ A__ _ _ _ _ _ _ _ _ _ __-_ __I_ __I_ _ _ _ _ _ _ N . - - I - -v 10 verMM I 1.210F-01 Vent

MARK II

CENTRAL ESTIMATE

MSL BREAK

NOT THROTILED

SPRAYS OPERATED

FIBROUS INSULATION

0.55 |

Enclosures 12 12.200E-03 f Enclosures

o.tJ

Waterborne 3 1.320E-02 Vents _

Drywell Floor I1.0,

0.06 iSedrment 4 0.000E+00 Floor -----------. _ r 0.00

Waterborne 5 6.600E-05 Vents

1.00_ _ _ _ _ _ _ I _ _ __ _ _ _ _

Sediment - . 6 0.000E+00 Floor

Condensate Drainage

0.01

Structures-Above

3.03 AAdheres Smnall Pieces

0.22

0.00

7 6.534E-03 Structures-Above 4- 4 -4. 0.99

Waterborne 8 1.980E-02 Vents

1.00

Recirulation Flow I

1.0 e 'Seddi nt_

0tructures-Break I- - - -I 0.00

3.09 iAdheres

t__________ 9 0.000E+00 $ Floor

10 0.000E+00 Stcrutcies-Break _ _ _ _ _ _ _ - _ _-- 0.(X)

Waterborne I1 2.860E-02 Vents

1.00

Sprays/Condensate I

0.50 iSediment

Structures-)ther 0.00

0.26 Adheres

t _ 12 0.000E+00 Floor

13 2.860E-02 Structmres-Other

Strucnturs-Breaic

0.15

Large-Above

0.34

StructusOtber

0.85

0.50

Wateroorne 14 4.080E-03 Vents

1.00

Recirculadon Flow

0.08 Sedint 15 O.E+00 Floor

0.00

Adheres 16 4.692E-02 Structures-Break

0.92

Waterborne 17 2.890E-03 Vents

1.00

Sprays/Condensate

0.01 Sediment 18 0.000E+00 Floor

Adheres 19 2.861E-01 Structures-Other

,MSL Break

1.00

0.99

Advected to Vent 20 3.600E-02 Venti

Enclosures 21 4.000E-04_ Enclosures

Large-Below

0.04

0.01

Waterborne 22 I .600E-03 Vents + 4 4

Drywell Floor I1.00

. .

0.04 'Sediment 23 1 0.000E+00 Floor

0.00

Waterborne 24 2.000E-04 Vents

1.00

aSedir.ent 25 0.oOOE+00 Floor

Recirculabion Flow

0.50

Structures-Break

0.01 Adheres

0.00

26 2.000E-04 Structures-Break _ .- . - --

0.50

Waterborne 27 1.600E-05 Vents

1.00

Sprays/Condensate

0.01 *Sediraent

Structures-Other 0.00

0.04 Adheres

........... I28 a .OOOE+00 Floor

29 I .584E-03 Structures-Other 4 _ . I 0.99

Canvassed 30 4.000F-OI Stnc-tulre/Flonr 5 1.... I 0 40 T+I I - ^C An ________________ "'' L ___

NUREG/CR-6369 A-40
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MIARK II

Estimate: CENTRAL ESTM F IBROU S INSIJLATION

Break. MSL BREAK

ECCS: NOT THROTTLED

SPRAYS OPERATED

TREE QUANTIFICA IION

Debris Classification Vents Enclosures Floor Structures Structures Structures Transport Above Break Other Fraction

Small Pieces 1.827E-01 2.200:E-03 O.OOOE+00 6.534E-037 O.OOOE+00 2.860E-02 0.8303

Large Pieces-Above 6.970E-03 0 O.OOOE+00 0 4.692E-02 2.861E-01 0.0205

Large Pieces-Below 3.782E-02 4.000E-04 O.OOOE+00 0 2.000E-04 1.584E-03 0.9454

All Large Pieces 4.479E-02 4.000E-04 O.OOOE+00 0 4.712E-02 2.877E-01 0.1179

All n T) 17;A-Al ) 4MP-01 n rnnF4-)n A 19FJA' 4 A7lPJ I 1 ARA- fl 2701

All Zone-of-Influence 0.2275

FINAL DISTRIBUTIONS (Horizontal) . .

Debris Classification Vents Enclosures Floor 31ruclures

Above

tructures Structures

Break Other

Small Pieces 83.03% 1.00% 0.00% 2.97% 0.00% 13.00%

Large Pieces-Above 2.05% 0% 0.00% 0% 13.80% 84.15%

Large Pieces-Below 94.54% 1.00% 0.00% 0% 0.50% 3.96%

AU Large Pieces 11.79% 0.11% 0.00% 0% 12.40% 75.71%

Al Debris 37.91% 0.43% 0.00% 1.09% 7.85% 52.72%

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Structures Structures Structures Above Break Otherl

Small Pieces 80.31% 84.62% N/A 100.00% 0.00% 9.04%

Large Pieces-Above 3.06% 0% N/A 0% 99.58% 90.46%

Large Pieces-Below 16.63% 15.38% N/A 0% 0.42% 0.50%

All Large Pieces 19.69% 15.38% N/A 0% 100.00% 90.96%

Debris Transport Fractions

1.000

0.750 4-

0

U

U.

0.500 4-

0.250 t0.000 -1- _ I I

Small Debris Large Above Large Below All Large Debris

Gratings Grabings

All Debns All Zone-ofInfluence

A-41 NUREG/CR-6369
Appendix A

A.3.2.2 Recirculation Line Break

This section contains central estimate logic charts for Mark 11 recirculation line break scenarios.

A43 NUREG/CR-6369
Appendix A

LOCA Type IDebris Clusufication -Distribution After IFroiacaddondo. O -- 1own. Ersinan a dwnDrw- or oI Pt olLct

Advected to Vents 1 1.078E-01 Vents

MARK 11

CENTRAL ESTIMATE

RL BREAK

ECCS THROTTLED

NO SPRAYS

FIBROUS INSULATION

Small Pieces

10.2

0.49 _ Enclosures 2 2.200E-03 Enclosures

u.u1

Watetbotre 3 5-SOE-42 Vents + n_ i_

Drywell Floor ILLK)

0.25 Sedinent

0.00

Waterbor

1.00

Condensate Drainage

0.01 Sediment

Structures-Above 0.00

o.01 Adheres

4 0.O0E+00 Floor

rne 5 2.200E-05 Vents

6 0.000E+00 Floor

7 2. 178E-03 Stractures-Above 4 .1 0.99

Waterbom

1.00

Recirculatron Flow

1.00 'Sedirnent

Strictures-Break 0.00

0.060

IC 8 1.320E-02 Vents

- 9 j .000Ec00 Floor

10 0.000E+00 Structures-Break -- __---------------- _--------- _ I

Waterborne 11 3.960E-04 Vents

1.0v

Condensate Drainage

0.01 iSediment

Stractures-Other 0.00

0.18 Adheres

1 12 0.000E+00 Floor __________

13 3I 0El2F.. qm,,h.-X~ther _. . v

Structures-Break

0.15

Large-Abvove

0;34

,Structvs-ther

0.85

0.99

Waterbome 14 4.080E-03 Vents

1.00

Recirculation Flow

0.08 Sediment 15 0.000E+00 Floor

0.00 -

Adheres 16 4.692E-02 Structures-Break

0.92

Waterbme 17 0.000E+00 Vents

11.00

Condensate Drainage i

10.00 ;Sedirnnt 18 0.000E+00 Floor A __________________ 0.00

A~rs19 2. 890E-01 Structures-Other

RL Break

1.00

1.00

Advected to Vent 20 3.600E-02 Vents

0.90t 1 Enclosures 21 4.000E-04 Enclosures

Large-Below

0.04

J.u0

Waterborne 22 I .600E-03 Vents 4 4 +

Drywell Floor I1.00

0.04 [Sediment 23 O.OOOE+00 Floor

0.00

Waterbonie 24 2.000E-04 Vents

1.0F

Sediment 25 0.OOOE+00 Floor

Recirculation Flow

0.50

Structures-Break

0.01 Adheres

0.00

26 2.0OOE-04 Structures-Break 4 I. 0.50

Waterbome 27 0.000E+00 Vents

:1.00

Condensate Drainage I

I0.00 - Sediment

Structures-Other | 0.00

0.04 {Adheres

__________ 128 0.000E+00 Floor

29 I .wnp-w3 Str--tums{)ther

. AA _L -. ... _ _ _ _ _ _ _ _ _ _

Canvassed 30 4.000E-01L Structures/Floor

A0.40 7 - I I -V,) fF I

NUREG/CR-6369 A-44
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: NIARK II

Estimate: CENTRAL ESTIMA FIBROUS INSULATION

Break. RL BREAK

ECCS: ECCS THIROTTE

SP ravs: NO SPRAYS

TREE QUANTIFICA TION

Structures Structures Structures Trnpt

Debris Classification Vents Enclosures Floor Aboue Brea Other Above Break Other Fraction

Smll Pieces 1.764E-01 2.2+0 0.0 0 2.178E-03 0. +00 3.920E-02 0.8019

Large Pieces-Above 4.080E-03 2 0.%0 +00 0 4.692E-02 2.8905-01 0.0120

Large Pieces-Below 3.780E-02 4.5% 1E-04 O.OOOE+00 0 2.50E-0%4 1.600E-03 %.9450

All Lar e Pieces 14.188E102 4.0E-04 O.OOOE+00 0 4.712E-02 72.906-01 0.1102

All Debris 2.183E-01 2.600E-03 O.OOOE+00 2.178E-03 4.712E-02 3.298E-01 03638

All Zone-of-Influence 0.183

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification Vents Enclosures Floor Structures Structures t e Above Break Other

Small Pieces 80.19% 1.006% N/A 0.99% 0.00% 11.89%

Large Pieces-Above 1.20% 0% 0.00% 0% 13.80%

Large Pieces-Below 94.50% 1.00% 0.00% 0% 0.50%

AU Large Pieces 11.02% 0.11% 0.00% 0% 10.00% 76.47%

All Debris 36.38% 0.43% 0.00% 0.36% 7.5_

RELATIVE CONTRI[BU711ONS ( Vertical

Debris Classification Vents Enclosures Transpor StFractions Above Break Othe

Small Pieces 80.82% 84.62% N/A 100.00% 0.00% 1.9

Large Pieces-Above 1.87% 0% N/A 0% 99.58% 8.3

Large Pieces-Below 117.32% 115.38% N/A 0% 0.42% 0_9

All Large Pieces 19.18% 15.38% N/A 0% 100.00% 88.11%

Debris Transport Fractions|

1.000 1

0.750

0

5 0.500 l

LL

0.250

0.000

Small Debris Large Above Large Below All Large Debris All Debris All Zone-ofGratings Grafings Influence

A-45 A-45 NUREG/CR-6369
Appendix A

Distribution -at I________ LOCA Type Debris Classificatdo DsrutoAfter F - Dy l lor P ao t rciohia Lcto 1 lwon Erosion and Wsshdow. ~orP ol Nrwi . rcin FnlLcto

I IrniNo t--uvea to venta I IL.R78-AI V.."

MARK II

CENTRAL ESTIMATE

RL BREAK

ECCS THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

0.49 . ' 

n r2 2.200E-03 Enclosures

u.UI

Waterbome 3 5.500E-02 Vents I. .

Dtywell Floor I1.00 t 0.25 iSediment 4 O.OOOE+OO3 M-~ -..- ___________ .I w

Waterbome 5 2.200E-05 Vents

ISediment 6 0.OOOE+00 Floor

Condensate Drainage

0.01

Situctures-Above

).01 Adheres Small Pieces 0.00

7 2. 178E-03 Statwues.-Above

0.99

Watertbome 8 1.320E-02 Venbs

1.00

Recuculation Flow I

LOO0 'Sediment

Structures-Break 0.00 1 I _0.00 3.06 jAdheres

,_________ __ __________ _O _ _

i0 O.OOE+O ShlthlRnuL __ _ - -. - - UI;V - - - - -w-

- - ----- ______ _ -

Waterbomne II 1.980E-02 Venbs

1.00

Sprays/Condensate

0.50 'Sediment

htuctus-Other 05 _ I 0.00

0.18 Adheres

t _ _ I

----- 12 1 0.000E+00 Floor

13 1.980E-02 Shnctumw~tbe

Structres-Break

0.15

Large-Above

0.34

Structtues-Otber

0.85

Advected to Vent

0.50

Waterbone 14 4.080E-03 Vents

1.00

Recirculation Flow

0.08 iSeduient I5 0.000E+00 Floor

Adheres 16 4.692Eu02 Structures-Break

0.92

Waterbone 17 2.890E-03 Vents

1.00

Sprays/Condensate

0.01 Sediment 18 0.OOOE+00 Floor

0.87 lAdheres -------- 2.861E3-01 Smxucmre-Other

RL Break

1.00

0.99

20 3.600E-02 Vents

D.90

Enclosures 21 4.000E-04 Enclosures

Large-Below

0.04

J.0i

Waterbome 22 1.600E-03 Vents I I _ I *_

Drywell Floor 11.00

'.04 !Sedhment 23 0.000E+00 Flor !_____ _____ ____F l r 0.00

Waterborne 24 2.000E-04 Vents

iSediment 25 0.000E+00 Floor

Recirculation Flow

0.50

Structures-Break

0.01 Adheres 0.00

26 2. mOF0n Itcu>ra i i -- , 4.i U.5u

Waterbome 27 I .600E-05 Vents

1.00

Sprays/Condensate

0.01 ,Sediment

Sthutures-Other 0._______________

0.04 Adheres

I 281 0.00E+O0 Floor

29 I1594F-03 Stu-es -,Other

-. i ---- --- 4 0.99

Canvassed in A (V0FOl AA - I .V -V II r r

0 4,Aj

1 - ---- -- I_____ tl I ._AA _ _ 

NUREG/CR-6369 A-46
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK _I

Estimate: _ _

Break: RLBREAK

ECCS: ECCSTHRO

S ra : SPRAYS OPERATED

TREE QUANTIFICATION

- ~Structures rStructures Structures Transport

Debris Classification Vents Enclosures Floor Above Break Other Fraction

_Small Pieces 1.958E-0l 2.200E-03 I 0.OOOE+0O 2.178E-03 O.OOOE+OO 1.980E-02 0.8901

Large Pieces-Above 6.970E-03 (I ,

t I-

O 4.692E-02 2.861E-01 0.0205

O 2.OOOE-04 I 1.584E-031 0.9454 -_ , _

-

T Arge Pieces-Below 3.782E-02 -- - 4 .

All Large Pieces 4.479E-02 4.vYUE 0 4.712E-02 2.877E-01 0.1179 w _

All Debris 2.406E-01 2.6(

All Zone-of-InflUence

FINAL DISTRIBUTIONS (Horizontal)

)OE A"1- ' 17;.A I 0.4010

n i^flK

Y - I

Debris Classification Vents Enclosures Floor Structures Structures

Above I Break

Structures

Other

Small Pieces 89.01% 1.00% 0.00% 0.99% 0.00% 9.00%

Large Pieces-Above 2.05% 0% 0.00% 0% 13.80% 84.15%

Large Pieces-Below 94.54% 1.00% 0.00% 0% 0.50% 3.96%

AU Large Pieces 11.79% 0.11% 0.00% 0% 12.40% 75.71%

All Debris 40.10% 0.43% 0.00% 0.36% 7.85% 51.25%

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Above StBreak Other

Small Pieces 81.39% 84.62% N/A 100.00% 0.00% 6.44%

Large Pieces-Above 2.90% 0% N/A 0% 99.58% 93.05%

Large Pieces-Below 15.72% 15.38% N/A 0% 0.42% 0.52%

All T -- Tie.- 1 R AI % I15.38/ N/A 0% l lWUM0 9J.D()_/0 -' -*ar- r. , . -.. - . -

Debris Transport Fractions

1 000.

0.750

0

Z 0.500 -

U. co

0.250 4-

0.000 - _ I r-I

Small Debris Large Above Large Below All Large Debris

Gratings GraUngs

All Debris All Zone-ofInfluence

A-47 NUREG/CR-6369
Appendix A

LOCA Type Debris Classificatoi itiuinfe Erosion and Wasbdown Drywell Floor Pool No.th Fraelson I FInal Location

Advected to Vents I 1.078E-01 Vents

MARK II

CENTRAL ESTIMATE

RL BREAK

NOT THROTTLED

NO SPRAYS

FIBROUS INSULATION

0.49 2 2.200E-03 Enclosures

0.01

Waterborne 3 5.500E-02 Vents * 1* 1.

Drywell Floor I1.00

0.25 iSediment

0.00

Waterborn

1.00

Condensate Drainage

0.01 , Sedunent

Structues-Above 0.00

0.01 Adheres

4 0.000E+00 Floor

e 5 2.200E-05 Vents

I 6 0.000E+00 Floor

Small Pieces

10.22

7 2.178E-03 Structures-Above

0.99

Waterbome 8 1.320E-02 Vents

1.00

Recirculation Flow

1.00 Sediuent I- Structures-Break 0.00

0.06 Aderes

I __________ 9 0.00E3+00 Floor

10 0.OOOE+O0 Structures-Break

0.00

Watesbome 11 3.960E-04 Vents

Condensate Drainage

0.01 iSediment

Structures-Other 0.00

0.18 Adheres

12 1 0.000E+2 RFloor

13 3.920E-02 Structures-Other

Structures-Break

0.15

Large-Above

0.34

Structures Ohe

0.85

Adveeted to Vent

0.99

Waterbome 14 1377E-02 Vents

1.00

Recirculation Flow

0.27 iSediment 15 O.O00Et00 Floor

0.00

Adheres 16 3.723E-02 Structures-Break

0.73

Waterborne 17 O.000E+00 Vents

11.00

Condensate Drainage 1

-I3-- 1 -0.00 - Sediunent 18 0.OO0E+00 Floor

0.00

Adhes 19 2.890E-01 Structures-Other

RL Break

1.00

1.00

20 3.600E-02 Vents

0.90

Enclosures 21 4.OOOE-04 I Enclosures T _ Dl_... I

ge-low |

0.0 1

Waterbome 22 I .600E-03 Vents

I1.00 Drywell Floor

0.04 ISediment 23 0.OOOE+00 Floor

Waterbome 24 2.OOOE-04 Vents

i Sedmient 1.00 - ---- _____ 25 25 0.000E+00 I Floor Floor

Recircuilation Flow

StruAturs-Break 0.50

0.01 Adheres

0.00

26 2.000E-04 Structures-Break

0.50 ______ +

Waterbome 27 0.000E+00 Vents

i 1.00

Condensate Drainage I

:0.00 ,Sediment

Structures-Other a . - -

0.04 Adheres

_ 28 [ O.0OOE+00 I Floor

29 1.600E-03 Structures-Other . _ _

1.00

Canvassed 30 4.OOOE-01 StructuresfFloor

0n40 Total 1 .OO 4.flf b h -

NUREG/CR-6369 A-48
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK II

Estimate: CENTRAL ESTIMA FIBROUS INSULATION

Break. RL BREAK

ECCS: NOT THROTTLED

Sprays: NO SPRAYS

TREE QUANTIFICATION

i EStructures Structures Structures Transport

Debris Classification Vents Enclosures Floor Above Break Other Fraction

Small Pieces 1.764E-01 2.200E-03 0.000E+00 2.178E-03 O.OOOE+00 3.920E-02 0.8019

Large Pieces-Above 1.377E-02 0 0.OOOE+00 0 3.723E-02

Large Pieces-Below 2.-OOE-04

2.890E-01 0.0405

1.600E-03 0.9450

2.906E-01 0.1357

1 -- o ra l I .. All Large Pieces

All Debris

All Zone-of-Influence

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Dehris i-iRELATIVE CONTRIBUTIONS (Vertical)

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All TLrpe Pieces 1 - - _____________ I -

Debris Transport Fractions

1.000

0.750

0

t 0.500 in

LA.

0.250

0.000 _ I

I,

Small Debris Large Above Large Below All Large Debris All Debris All Zone-ofGrafings Grabings Influence

A-49 NUREG/CR-6369
Appendix A

LOCA Type Debris Cusificato, Dstibution Ir Erosion and WashdWn DryPl Floor Pool ath Fraction Final Location

I lowdown I No.I

Advected to vents I 1.078E-01 Vents

MARKI1

CENTRAL ESTIMATE

RL BREAK

NOT THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

2.49

Enclosures 2 2.200E4.03 Enclosures

2.01

Waterbone 3 5.500E-02 Vents -I- _ _ _ _ _ _ _ _ _

Drywell Floor I1.00

_ ).25 Sedinent

0.00

Waterbon

1.00

Condensate Drainage

0.01 Sedirent

Structures-Above 0.00

2.01 Adheres

4 0.000E+00 Flwr

e 5 2.200E-05 Vents

=. 6 e000E4+00 Floor

Snml Pieces

0.22

7 2.178E-03 Structure-Above + + 0.99

Waterbome 8 1.320E-02 Vents

1.00

Recuculabion Flow

1.00 'Sedu ent Strcues-Break 0.00

2.06 Adheres

,t_________ 9 0.000E+00 Floor

10 0.000E+00 Structures-Break

0Strctu ter18

0.18

9nt um-1reak

0.15

Large-Awove

0.34

lStructurtber

0.85

0.00 --------- ___ Waterbome II 1.980E-02 Vents

100

Sprays/Conderate |

0.50 n- 12 0.000E+00 Floor

0.00

Adheres 13 1.980E-02 Structures-Other

Waterborne 14 1.377E-02 Vents

1.00

Recireulation Flow 1

0.27 Sedinent 15 0.000E+00 Floor

lAdheres 16 3.723E-02 Structures-Break

0.73

Waterborne 17 2.890E-03 Vents

1.00

Sprays/Condensate 1.00

0.01 Sediment 18 0.000E+00 Floor

Adheres 19 2.861E-01 Structures-Other

RL Break

1.00

0.99

Advected to Vent 20 3.600E-02 Vents

Enclosures 21 4.000E44 Enclosures

Large-Below

0.04

0.01

Waterborne 22 1.600E-03 Vents

Drywell Floor

11.00

0.04 ISediment 23 0.OOOE+00 Floor

0.00

Waterbome 24 2.000E-04 Vents

1.00 i _ _

iSedinent 25 0.000E+00 Floor

Recirculation Flow

0.50

Strmtures-Break

0.01 Adheres

0.00

26 2.000E-04 Structures-Break _

0.50

Waterbone 27 1.6002-05 Vents

1.00

Sprays/Condensate

0.01 Sedinmnt

Structures-Other 0.00

0.04 Adheres

-[ 28 0.000E+00 Floor

29 1 .584E-03 Structures-Other _

_ 0.99

Canvassed

A _ 30 400fWF-01 SIructres&Flnfr r

-- ._---- -- 4 0.40 Total I I nmv:14,o

NUREG/CR-6369 A-50
Appendix A

I

DEBRIS TRANSPORT RESULTS I

Plant Design:

Estimate:

Break:

ECCS:

Sprays:

TREE QUANTIFICCA

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

All Zone-of-Influence

FINAL DISTRIBUTI

.CENTRAL ETM I _RUS INSULATION

RL BREAK|

NOT THROTTE

SPRAYS OPERATED

LTION

. et nlsue lo Structures Structures Structures Transport Vents Enclosures Floor Above Break Other Fraction

1.958E-01 2.200E-03 O.OOOE+00 2.178E-03 0.000E+00 1.980E-02 0.8901

1.666E-02 0 O.OOOE+00 0 3.723E-02 2.861E-01 0.0490

3.782E-02 4.000E-04 O.OOOE+00 0 2.OOOE-04 1.584E-03 0.9454

5.448E-02 4.OOOE-04 O.OOOE+00 0 3.743E-02 2.877E-01 0.1434

2.503E-01 2.60013-03 O.OOOE+00 2.178E-03 3.743E-02 3.075E-01 0.4172

LONS (Horizontal)

Vents Enclosures Floor Structures Structures Struc

Above Break Other

89.01% 1.00% 0.00% 0.99% 0.00% 9.00%

4.90% 0% 0.00% 0% 10.95% 84.15%

94.54% 1 .00% 0.00% 0% 0.50%

14.34% 0.11% 0.00% 0% 9.85%

41.72% 0.43% 0.00% 0.36% 6.24%

UBUTIONS (Vertical)

_ -Structures Structures Structur

V Above Break Other

78.24% 84.62% N/A 100.00% 0.00% 6.44%

6.66% 0% N/A 0% 99.47% 93.05%

15.11% 15.38% N/A 0% 0.53% 0.52%

21.76% 15.38% N/A 0% 100.00% 93.56%

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

RELATIVE CONTI

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

Debris Transport Fractions

1.000 

1

0.750

tS0.500

U.

0.250

0.000

Small Debris Large Above Large Below All Large Debris All Debris All Zone-ofGratings Grabngs Influence

A-51 A-51 NUREG/CR-6369
Appendix A

A.3.3 Mark III

This section contains the central estimate logic charts for the Mark IlIl design.

A.3.3.1 Main Steam Line Break

The central estimate logic charts for the main steam line breaks are presented here, then the charts for

the recirculation line breaks are presented in Section A.3.3.2

A-53 NUREG/CR-6369
Appendix A

LOCA Type Debris Classificatin Distribution After Erosion and Washdown Drywell Floor Pool Path Fracdon Final Locao

I -_ i -Blowdown I INo. Io n c i -- - -11. I 1 1.210E-0n1 1 V..ft

MARK III

CENTRAL ESTIMATE

MSL BREAK

ECCS THROTTLED

NO SPRAYS

FIBROUS INSULATION

1 itlt.fl I I ---

).55 . - Encloses3 Enclosures

J.uJ

Waterbome 3 0.000E+00 Vents . -- -- - -- _ _ __- .

Drywell Floor

i0.00

I

0.01 I edunent 4 2.200E-03 FT-,

1.00

Wate __ome 5 0.000E+O0 Vents

dirent 6 6.600E-05 Floor

Condersate Drainage

0.01

Structures-Above

0.03 Adheres Stmall Pieces

0.2

LOU0

7 6.534E-03 Stmuctun s-Above

Structures-Above 0.99

Waterbome 8 0.000E+00 Vents

10.00

Condensate Drinage !

0.01 Sediment

Structures-Break 1.00

0.10 ]Adheres

2.200E-04 Flor

10 2. 78E-02 qStrilct Res-re 10 2175F.X12 0.99

Waterbome 11 0.OOOE400 Vents

10.00

Condensate Drainage |

0.01 ISecliment

Structures-Other 1.00

0.30 Adheres

t123 6.600E-04 Floor

13 6.534E-02 Stmctures{)ther

StrucftusBreak

0.15

Large-Above

0.34

Structures-Other

0.85

0.99

Wateebomne 14 0.OOOE+00 Vents

:0.00

Condensate Drainage !

i0.00 Sediment 15 0.000E+00 Floor

1.00

Adheres 16 5.100E-02 Structures-Break

1.00

Waterbomne 17 0.000E+00 Vents

Condensate Drainage i

:0.00 - Sedirnt 18 0.000E+00 Floor

Adheres 2.89001 Strctures-Other

MSL Break

1.00

1.00 Advected to Vent 20 3.600 E-0 Venh _ ._ _ __ .I w

0.90 _ Enclosures [ 21 4.000E-04 I Enclosures

Large-Below

0.04

0.01

Waterbone 22 O.OOOE+00 Vents ! -I---------- r - I ,0.00

Drywell Floor _, . _. ;

0.04 _ISedimnt 23 I .600E-03 Floor

1.00

Waterborne 24 0.000E+00 Vents

10.00

'Sedimnent 25 O.OOOE+00 Floor I o

Condensate Drainage

10.00

Structures-Break i

01 |Adheres

1.00

26 4.000E3-04 Structures-Break I -- I4 - _ 1.00

Waterbome 27 0.OOOE+00 Vents

10.00

Condensate Drainage I

0.00 - jSediment

Structures-ther 1.00

0.04 IAdheres

_28 O.OOE+00 Floor

29 I .600E-03 Structures (hher ____ I. Structures-Other 1.00

Canvassed 30 4.0001-01 ;t. S hlm^sEM,

In - ir; S n 11. __v |.. l ___ ...... ~ I nn, [I 

NUREG/CR-6369 A-54
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK m

Estimate: CENTRAL ESTIMA FIBROUS INSULATION

Break: NISL BREAK

ECCS:ECCSTHRO

Sprays: NO SPRAYS

TREE QUANTIFICATION

_ _j_ IStructures Structures Structures Transport Debris Classification Vents Enclosures Floor Above Brea Other Fracspon S Above Break Other Fraction

Srmll Pieces1.1E0 2.200E-03 I3.146E 03 I6.534E-03 I2.178E 02 I 6.534E-02 0.5500

Large Pieces-Above 0.000E+00I 0

lOE-04

0.OOOE+00

FINAL DISTRIBUTIONS (Horizontal)

I - I - RELATIVE CONTRIBUTIONS

Debris Transport Fractions

1.000

0.750

0

U.

0.500 ---

0.250 4-

0.000 -

Small Debris

I l _ I _

Large Above Large Below All Large Debris

Gratings Gratings

All Debris All Zone-ofInfluence

A-55 NUREG/CR-6369
Appendix A

LOCA _Type____Ctcatton| DistriBu d _ |tErosion andPWashdow| F o,, P°°i_|N PathLoat- | ractton | 

LOCA Type IDebris CQusflC2 Dtrbldown A Ier Erosion and Wasbdowni Drywell Floor Pool Fraction I Final Location

Advected to Vents I 1.21OE-01 Vents

MARK III

CENTRAL ESTIMATE

MSL BREAK

NOT THROTTLED

NO SPRAYS

FIBROUS INSULATION

Soall Pieces

10.22

)55 | 2

Socloasres 1 2 1 2.200E-03 I Enclosures

).01

Waterbome 3 .760E-03 Vents

1 1 -4

Drywell Floor

I0.80

).01 ISedirnent 4 4.400E-04 Floor

0.20 _

Waterbome 5 5.280E-05 Vents

Sedinent 6 1.320E-05 Floor

Condesate Drainage

0.01

Strwtures-Above

0.03 ]Adheres

0.20

7 6.534E-03 Structures-Above t 5 + 0.99

Waterborne 8 1.760E-02 Vents

0.80

Reciculation Flow

1.00 Sedinent

Strwtures-Break 0.20

0.10 tAdheres

- I 4I 40003 Floor

10 0.0O0E+00 Structures-Rreak

0.00------------------------ 0.00

----- I I _ _

Wateroorne 11 5.280E-04 Vents

0.80

Condensate Drainage

0.01 Sedirnent

Strctures-Other 0.20

0.30 Adheres

= 12 _ 1.320E-04 Floor

13 6.534E-02 Structures-Other

Strucu-Break

0.15

Large-Above

0.}4

Straxtules-Otber

0.8S

Advected. to Vent

0.99

Wateroome 14 4.080E-03 Vents

1.00

Recirculation Flow

0.08 tSedirnent 15 0.000E+00 Floor

0.00

Adheres 16 4.692E-02 Structures-Break

0.92

Waterborne 17 0.000E+00 Vents ,____________-.-

Condensate Drainage I

0.00 Sediment 18 0.000E+00 Floor

|Adheres 19 2.890E-01 Structures-Other

M1SL Break

1.00

1.00

20 3.600E-02 Vents

0.90 21

Enclosures 21 14.OO0E-04 I Enclosures

Lrge-Below

0.04

0.01

Waterbome 22 O.OOE+00 Vents

;0.00

Drywell Floor i_. -

0.04 pediment 23 1.600E-03 Floor

1.00

Waterbornme ------- 24 0.OOOE+00 Vents

ISedinent 25 2.000E-04 Floor

Recirculation Flow

0.50

Stxtures-Break

0.01 Adheres

1.00

26 2.000E-04 Structures-Break 4 __I 0.50

Waterbome 27 O.OOOE+00 Vents

j0.00

Condensate Drainage ,

10.00 ISed t

Structures-Other .00 .

0.04 lAdheres

28 i 0.000E+00 Floor

29 1.600E-03 Structures-Other 4 4

Canvassed 30 4.000E-0^l StructresMFloor I - - I -

1 Al) TAIPEI I -A-,,;JA u~eu _ _ .........

NUREG/CR-6369 A-56
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK ITT

Estimate: CENTRAL ESTFIBROUS INSULATION

Break MSL BREAK|

ECCS: NOT THROITLED

Sprays: NO SPRAYS

TREE QUANTIFCATION|

Debris Classification Vents Enclosures Floor Structures Structures Structures Transport Above Break Other Fraction

Strnall Pieces 1.409E3-01 2.200E-03 4.985E-03 6.534E-03 O.OOOE+005 6.534E-02 0.6406

Large Pieces-Above 4.080E-03 0 O.OOOE+00 0 4.692E-02 2.890E-01 0.0120

Large Pieces-Below 3.600E-02 4.OOOE-04 1.800E-03 0 2.000E-04 1.600E-03 0.9000

All Large Pieces 4.008E-02 4.OOOE-04 1.800E-03 0 4.712E-02 2.906E-01 0.1055

All Debris 1 8O1P-02l 9600P-03 6 7R8P-03 534E-03 4. 71'Rfl9 3 % iqp-ni n f1'7

0.1810

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification Vents EnclosuresI Floor Structures

Above

tructures I Structures

Break Other

Small Pieces 64.06% 1.00% 2.27% 2.97% 0.00% 29.70%

Large Pieces-Above 1.20% 0% 0.00% 0% 13.80% 85.00%

Large Pieces-Below 90.00% 1.00% 4.50% 0% 0.50% 4.00%

Al Large Pieces 10.55% 0.11% 0.47% 0% 12.40% 76.47%

AUl Debris 30.17% 0.43% 1 1.13% 1.09% 1 7.85% 59.32%

RELATIVE CONTRIBUTIONS (Vertical

Debris Classification Vents Enclosures Floor Structures StruBtures Structures Above Break Other

Small Pieces 77.86% 84.62% 73.47% 100.00% 0.00% 18.36%

Large Pieces-Above 2.25% 0% 0.00% 0% 99.58% 81.19%

Large Pieces-Below 19.89% 15.38% 26.53% 0% 0.42% 0.45%

Al Large Pieces 22.14% 15.38% 26.53% 0% 100.00% 81.64%

Debris Transport Fractions

1.000

0.750

Z 0.500 -

U.

0.250 -

0.000 -

Small Debris

I _ i I _

Large Above Large Below All Large Debris

Gratings Gratings

All Debris All Zone-ofInfluence

A-57 NUREG/CR-6369
Appendix A

A.3.3.2 Recirculation Line Break

This section contains central estimate logic charts for Mark 1II recirculation line break scenarios.

A-59 NUREG/CR-6369
Appendix A

LOCA Type |Debrbc~fic o stBluodn I Erosion and Wasbdown Drywell Floor Pool Fraction Final Location

Advected to Vents I 1.078E-01 Vents

MARK III

CENTRAL ESTIMATE

RL BREAK

ECCS THROTTLED

NO SPRAYS

FIBROUS INSULATION

Small Pieces

10.22

0.49

Enclosures 2 2.200E-03 Enclosures

0.01

Waterbome 3 3.696E-02 i. I.

Drywell Floor 10.80

0.21 |Sedi-ment

0.20

Waterborn

0.80

Condensate Drainage

0.01 Sedirnent

Structures-Above 0.20

0.01 Adheres

4 9.240E403 Floor

e S 1.760E-05 Vents

: 6 4.400E-06 Floor

7 2.178E-03 Structures-Above F F F

0.99

Waterborne 8 1.232E-02 Vents

0.80

Recirculation Flow

1.00 Sediment

Structures-Break 0.20

0.07 jAdheres

- 9 3.080E-03 Floor

10 0.OOOE+00 Structures-Break -------- __________.

0.00

Waterborne I1 3.696E-04 Ventb

0.80

Condensate Drainage

0.01 Sedirent

Structures-Other 0.20

0.21 Adheres

2 _F

t12 9.240E405 Floor

13 4.574E-02 Structures-Other

Structures-Break.

0.15

Large-Above

0.34

Stractures Other

n.8s

Advected to Vent

0.99

Waterbome 14 4.080E-03 Vents

1.00

Recirculation Flow

0.08 Sedtnent IS 0.EOOO+00 Floor

0.00

_Adheres 16 4.692E-02 Strucnures-Break

0.92

Waterborne 17 0.OOOE+00 Vents

'1.00

Condensate Drainage I

:0.00 oSediment 18 0,OOOE+00 Floor Adhr... 19 _________ 0.00

1 dbre ....... 19 2. 890E4 1 Structures-Other

RL Break

1.00

1.00

20 3.600E.02 Vents

0.90

Enclosures 21 4.000E-04 Enclosures

Large-Below

0.04

D.01

Waterborne 22 0.OOOE+00 Vents -------- - - ----- I

iO.00

Diywell Floor

_ 

| A

0.04 ISediment 23 I .600E-03 Floor

1.00

Wateroome 24 O.OOOE+00 Vents

20.00

ISedimnent 25 2.OOOE-04 Floor

Recirculation Flow

0.50

Structurs-Break

0.01 : Adheres

I.00

26 2.000E-04 Structures-Break

0.50

Waterbome 27 0.00E+-OO Vents

10.00

Condensate Drainage i

:0.00 oSediment

Structures-Other 1 ---- 0.04 1Adheres

------ 28 I .OOOE+00 I Floor

29 I .600E-03 Structures-Other

1.00

Canvassed 30 4.OOOE-01 Structures/Floor + + F 0 40 T,1l I I .rV

NUREG/CR-6369 A-60
Appendix A

DEBRIS TRANSPORT RESULTS I

Plant Design:

Estimate:

Break

ECCS:

TREE QUANTIFICG

Debris Classification

Srnall Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

All Zone-of-Influence

FINAL DISTRIBUTI

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

RELATIVE CONTI

Debris Classification

Smnall Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

CENTRAL ES I A iR US INSULATION

_RL BREAK

_ECCS TIOTE

.NO SPRAYS|

_ MON

Vetnlsue lo Structures Structures Structures Transport

V Above Break Other Fraction

1.575E-01 2.200E-03 1.242E-02 2.178E-03 O.OOOE+00 4.574E-02 0.7158

4.080E-03 0 O.OOOE+0O 0 4.692E-02 2.890E-01 0.0120

3.600E-02 4.OOOE-04 1.800E-03 0 2.000E-04 1.600E-03 0.9000

4008E-02 4.OOOE-04 1.800E-03 0 4.712E-02 2.906E-01 0.1055

195-1 2600E3-03 1.422E-02 2.178E-03 4.712E-02 3.363E-01 0.3292

0.1975

[ONS (Horizontal)

Vents Enclosures Floor Structures Structures Structures

Above Break Other

71.58% 1.00% 5.64% 0.99% 0.00% 20

1.20% 0% 0.00% 0% 13.80% 85.

90.00% 1.00% 4.50% 0% 0.50% 4.

10.55% 0.11% 0.47% 0% 12.40% 76.47%

32.92% 0.43% 2.37% 0.36% 7.85% 56.06

.LBUTIONS (Vertical)

Structures Structures Structures

Vents Enclosures Floor Above Break Othe

79.71% 84.62% 87.34% 100.00% 0.00% 13.60

2.07% 0% 0.00% 0% 99.58% 85.93%

18.22% 15.38% 12.66% 0% 0.42% 0.48%0/

20.29% 15.38% 12.66% 0% 100.00% 86.40%

Debris Transport Fractions

I U(Hi)U

0.750

C0

U.

0.500 +-

0.250 _--

0.000 - _ r l l

Small Debns Large Above Large Below All Large Debris

Gratings Grafings

All Debris All Zone-ofInfluence

A-61 A-61 NUREG/CR-6369
Appendix A

fatn!Distribution After LOCA Type Debris ClawsiicdoErosion and Wabdownj Drywell Eloor Poo I path Lli Lc*o IBlowdown l--.- No.I Fraction InlLcto . - - - - I1 - - AUVeCi a to vents t I I 7SIVl01 V.n.

MARK III

CENTRAL ESTIMATE

RL BREAK

NOT THROTTLED

NO SPFAYS

FIBROUS INSULATION

Small Pieces

10.22

) 49

Enclosures I~2 2.200E3-03 Enclosures

0.01

Waterborne 3 13.696E-02 Venth

Drywell Floor

0.21 Sonn

0.20

Waterboro

0.80

Condensate Drainage

0.01 Sediment

3tructures-Above 0.20

).01 Adheres

4 9.240E-03 Flnr

loe 5 1.760E-05 Vents

t 6 4.400E06 Floor

7 2.178E-43 Structur-Above

_I 0.99

Waterborne 8 1.232E-02 Vents

0.80

Recirculation Flow I

LOO0 Sediment

StructmwBreak 0.20

0.07 A~ee

0.00

Watebomn

Condtensate ]Draioage 08

[0.01 Sedinlert

StruarresOther |0.20

(0.21 Adheres

9 3.080E-03 Floor

O.OOOE+00 Structures-Break __________. -.- -_-_

ie II 3.696E.04 Vents

_ 12 9.240E405 Floor

13 4-574F-2 S trvctunsq4ther

StructusBreak |

0.15

Large-Abovc

0.34

Stracturnsther

0.85

0.99

Waterborne 14 1.377E-02 Vents

1.00

Recirculation Flow I

0.27 iSe~dtrtelt 15 0.000E+00 Floor

1eres6 3.723E-02 Struectues-Break

0.73

Waterbrne 17 0.000E+OO Vents

11.00

Condensate Drainage I

10.oo ,Seduient 18 0.OOOE+O0 Floor

0.00

Abrs.19 2. 890E-01 StrictursOther

RL Break

1.00

1.00

Advected to Vent 20 1 3.600E-02 Vents

0.90 t

Enclosures L 21 4.0001E-04 I Enclosures

Large-Below

0.04

0.01

Waterbome 22 0.000E+00 Vents

'0.00

Diywell Floor

0.04 23 I 1.600E4J3 Floor

1.00

Waterbome 24 0.000E+00 Vents

_0.00 _ __ __

ISediuent 25 2.000E-04 Floor

Recirculation Flow

Strictures-Break |

0.01 Adheres

1.00

26 1 2.000E-04 Structares-Break

_ I StructBreak

0.50

Waterborne 27 0.000E+00 Vents

i0.00

Condensate Drainage 4 -- I 10.00 IScdinient

Structures-Other | 1. 0

0.04 Adheres

I------ 128 O.00E+00 I Floor

29 1.600E-03 Structures-Other

_ StractuOther 1.00

Canvassed 30 4.ODOE-01 Structures/Floor

4/d tal I I nOO+ - d

NUREG/CR-6369 A-62 A6
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MIARK m

Estimate: CENTRALE FIBROUS INSULATION

Break: RLBREAK

ECCS:NOTTHRO

Sprays: NO SPRAYS

TREE QUANTIFICATION

Debris Classification Vents Enclosures Floor Above Brea Other Fracspon Above Break Other Fraction

Small Pieces 1.575E-01 2.200E-03 1.242E-02 2.178E-03 O.OOOE+00 4.574E-02 0.7158

Large Pieces-Above 1.377E-02 0 O.OOOE+00 0 3.723E-02 2.890E-01 0.0405

Larce Pieces-Below 3.600E-02 4.000E-04 1.800E-03 0 1.600E-03

o -^n ns I .1 I

All Laree Pieces 4.977E-02 4.OOOE-04 1.800E-03 I 0

0.9000

0.1310 I 4 I

All Debris 2.072E-01 2.600EAll 7 II . nf Tnflnpnrce

FINAL DISTRIBUTIONS (Horizontal) . .

Debris Classification Vents Enclosures Floor structures Structures Structures

Above I Break I Other

Snall Pieces 71.58% 1.00% 5.64% 0.99% 0.00% 20.79%

Large Pieces-Above 4.05% 0% 0.00% 0% 10.95% 85.00%

Large Pieces-Below 90.00% 1.00% 4.50% 0% 0.50% 4.00%

All Large Pieces 13.10% 0.11% 0.47% 0% 9.85% 76.47%

All Debris 34.54% 0.43% 2.37% 0.36% 6.24% 56.06%

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Above Break Other

Small Pieces 75.98% 84.62% 87.34% 100.00% 0.00% 13.60%

Large Pieces-Above 6.64% 0% 0.00% 0% 99.47% 85.93%

Large Pieces-Below 17.37% 15.38% 12.66% 0% 0.53% 0.48%

All Large Pieces 24.02% 15.38% 12.66% 0% 100.00% 86.40%

Debris Transport Fractions

1.000

0.750

r_0

U_

0.500 _-

0.250 _-

0.000 4- _ I I ,_ l

Small Debris Large Above Large Below All Large Debris

Gratings Gratings

Al Debris All Zone-ofInfluence

A-63 ANUREG/CR-6369
Appendix A

A.4 LOGIC CHARTS FOR UPPER BOUND ESTIMATES

The logic charts for the upper bound debris transport estimates are presented here.

A.4.1 Mark I

This section contains the upper bound estimate logic charts for the Mark I design.

A.4.1.1 Main Steam Line Break

The upper bound estimate logic charts for the main steam line breaks are presented here, then the charts

for the recirculation line breaks are presented in Section A.4.1.2.

A-65 NUREG/CR-6369
Appendix A

LOCA Type Debris Clasificado Erosion and Wasbdown| Drywei ioor Pool | path | | It'I __Blowdown Irso n abomlDyelForPo No. Fraction Ml oao

IAAv,~tl - I- - I

MARK I

UPPER BOUND

MSL BREAK

ECCS THROTTLED

NO SPRAYS

FIBROUS INSULATION

A§.l t _SW I V_ V SUt_ I B958EOI v-n

0.89 _.

Enc-ff---________________________________. Enclourese 2 0.0 

w.w

Waterbome 3 0.wwOE+w0 Venht

!!n= ----------- --- -

Dryweml Floor !U.W

-- 4 - J.uw i eirnt 4 0.000E.+w Roor-

,________

Waterbom. _ 5 0.000E+00 Vents

0__.0006+00 Floor

Small Pieces

0.22

'.000

Condensate Drainage I

lo.10 ISedirnent

Strutrcet-Above i 1.

0.00 Adheres

t0.90e---_

Watetrbor

I- ~_ .--

Condensate Dralmage I

0.10 Sediment

Stmctures-Break 1.00

0.03 Aheres

7 0.00OF-(w Str__turevAh^ve ,_______ _ _ _

ne 8 0.ww0E+00 Venb

t9 6.600E Roo-r

10 5.94nE-03A qtn-uh,-n- k 1 - 5._ 4IJ 

U.9U

Waterbome 11 O.000E+00 Vents

iO.w

Condensate Drainage I

0.10 fSediment

Strutures-ther I1.00

0.08 Adheres

12 1.760-03 Floor

13 I1.584E-02 qtn^lcher)

Structures-Break

0.25

Large-Above

0.30

[Smiutures{)tber

0.75

0.90

Waterbome 14 0.000E+00 Vents

Condensate Drainage |

'0.00 Sedimnent 15 0.000E+00 Floor

1.00

lAdheres 16 7.50wE-02 Structures-Break

1.00

Waterbome 17 0.000E+00 Vents

r0.°-----------_ Corndensate Drainage I

i0.w -Sediment 18 0.000E+00 Floor

Adhers 2.250E-01 Structures-Other MASL Break

1.00

1L.W

Advected to Vent 20 8.0ME 02 V...

__ I.00 v I

Enclosures ___ 21 To .OOE+0o I F-1

Large-Below ----------------------------____.

0.08

10.00

Wateroome

------ i ~- ..- - I ----- _

22 0.000E+00 Vents I----------------- '0.00

°Sedir^ent 23 O.OOOE+00 Floor

1.00

Waterbome 24 0.00wE+00 Vents

iSedirnent 25 0.000E+00 Flr

Condensate Drainage

| '0.00

Structures-Break i

00 -- lAdheres 1.00

26 o.002E+00 Structwres-Break I---------------------- - _- _____ _____ 

1.00

Waterborne 27 O.OE00R4) Vent.

I '0.00

Condensate Drainage

* 0,0.0 ;Sedunent

iStructures-her O -

0.00 ."Adheres

__________ 28 O.OOOE+00 Floor

29 O.OOOE+00 Stnichim-q-0th-r -____________________________________ I _ _ I

Canvassed 30 4. 000E-01 I I I _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ __ -_ I _ -L- I W v~ -VOF0 = L I 11 -1 I~n ---- I:0 I oM ull I I AAX~thHJ() I

NUREG/CR-6369 A-66
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK I

Estimate: UPPER BOUND_ FIBROUS INSULATION

Break: MSLBREAK

ECCS: ECCS THRO

Sp~rays: NO SPRAYS

TREE QUANTIFICATION

ncloure Flor IStructuresl Structurv Structures Transport

Debris Classification Vents Enclosures Floor Above Break Other Fraction

Srall Pieces 1.958E-01 0.OOOE+00 2.420E-03 0.0OOE+00 5.940E-03 1.584E-02 0.8900

. - - A - n:_> -. n rdU^Vi'IM n) 0.000EF+00 0 1.5Wk)UtZU Z.L3Zttv 1 U

Large rlecs-#i.iuvvr 1 -- 1~~f A:::::

1 -0 i - _9_I7 i:OH:+_ I .U _k*1i J ~ ~ %v A1ArVU,

.UUUU

-

s nnnn r 1' -- R .000-02 0.000E+W0 0.vWh-i- u uAu ur uuV V, VkV V eVVI

1xargVc Ills-b~ I v vv __ _a - AA A ^rA

'''-" I - ---- -- I I - _ .

All r rae Pieces 8.000E-02 I 0.00OE+00 0.000E+Wj I u 2.250E-01

^ A4nRA-1l

0.2105

0.4597 All Debris 2.758E-01 0.W0E+v0

All Zone-of-Inluenc

FINAL DISTRIBUTIONS (Horizontal) . I

Debris Classification Vents Enclosures Floor tructures structures

Above I Break

structures

Other

Small Pieces 89.00% 1 0.00% 1.10% jo 0.00% I 2.70% 7.2

Large Pieces-Above 0.00% 0% 0.00% I 0% 25.00% / 75.

- . - __ I - I - I 'Nn- I . n I I _ __ _ n: _A D 1 At Z 1 AA nno,0 n1 MUo/A I ) I N I/. U/oA kU.VV70 Large rieces-nelow I V.VV/U u - -o vu ^ ta 7AO U.UtW/o P1, /Anl O

All T nroe Pieces 21.05% 0.0O% O W %/ 1Y. / /OO0

1^1 49°01 a --I 

All Debris 45.97% 0.00% Imi -

RELATIVE CONTRIBUTIONS (Vertical) I. -

Debris Classification Vents Enclosures I Floor

Structuresi Structures Structures

Above I Break I Other

Small Pieces 70.99% N/A 100.00% N/A 7.34% 6.58%

Large Pieces-Above 0.00% N/A 0.00% N/A 92.66% 93.42%

Large Pieces-Below 29.01% N/A 0.00% N/A 0.00% 0.00%

All Large Pieces 29.01% N/A 0.00% N/A 92.66%0 J 93.42%

1 2510

Debris Transport Fractions

1.000

0

U.

0.750 ±-

0.500 -_

0.250

0.000

Small Debri!

l ~~ l _ l

s Large Above Large Below Ail Large Debns

Gratings Gratings

All Debris All Zone-ofinfluence

A-67 NUREG/CR-6369
Appendix A

LOCA Type jDebrHsCissflation[ 1 D tribu d n After ErosionandWasbdown DrywelUFloor Pool I N | Fraction | Fnal Location d or w ahlo n F l a o c t o

WW Y .x, I 95IF "A- vv"s MARK I

UPPER BOUND

MSL BREAK

ECCS THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

Small Pieces

0.22

0.89 .

Enclosures - - -- - -- - -- - -- -E-clo-ures

n m 0 ----------- 2 

Waterborne 3 0.000E+00 -_- _ _ -3- _ _ -- v. v

Drywell Floor .0.00

Vents

Floor

;-- _ _ _- -- _ _ -- - _- -- -- - .2

o.UU ISediment

1.00

4 0.000E+00

Waterbome

,-________________

I'0.10

Condensate Drainage

.0.10 ,-Sedis et

Structues-Above I *----------

0 ° !9Adheres0

S 0.000E+00

6

Vents

Floor

Stnsctures-Above

L v

7

0.000E+00

L______________________________ -f - - - _____ - ____ w-- 

0.90-

Waterbon

Sprays/Condensate

1.00 Sediment

SWtn-s-Breakr 0.90

0.03 ,Adheres

0.00---_ _

Waterbovr

0.10

Sprays/Condlensate

1.00 [Sediment

0.08 Adbere

me 8 6.600E.-04 Vena

tI9 5940E-03 Floor

in 0 (Mpo~n --n- -1- .__________. v I v- wn cue

me 1 1 I1.760E03 V.et. 1_1 1_ . E-0Fo

__ _ _ _ _ 12 I1.584E..02 Flcor

13 0.000E+00 lztmc -- tuhe

StrwwresBreak

Large-Above

0.30

Str~ictures-0ther

0.75

0.00 ---------- _

Waterborne 14 1.500E-03 Vents

1.00

Sprays/Condensate

O.02 Sediment 15 0.OOOE+00 Floor

.Adheres 16 7.350E-02 Structures-Break

0.98

Wateabeome 17 4.500E-03 Vents

1.00

Sprays/Condensate

0.02 *Sedinent 18 0.000E+00 Floor

Adheres 19 2.205E-01 Strictures-Other MSL Break

I .00

0.98

Advected to Vent 20 8.000E'027 V.nh

-v 0 I -- vIc'

11.00

1s u E r e n sc l n - -- - t 0 .O E + 0 { n c o r e Lag-elow

0.08

i

Drywell Floor

Waterborne 22 O.OOOE400 Vents r----------------- I0.00

10.00 I 23 O.OOOE3+OO Floor

W atelborn_,___ 24 O.OOOE3+OO Venbs

I, -____- 2 5 O. OO1E+00 Fl oor

I Sprays/Condeensate

a i0.02

IStruc tures-8reak 1.

'0.00 !Aders

1.00

26 O (MF+(n StnztunsRrfflk !.n ------------------------------------- -- ^.w . u1'vV-I

U.9v

Waterbone_ 27 O.DOOOE+OO VentsA

I0.00

i Sprays/Condienate I

; 0.02 --- ;Sediment

!Structures4)ther 1 -,.00 -- 0.00 iAdhiere,

:.....[ 28 0.030E+OO Floor _

29 O.OOOE3+OO Smtrutrs-Other o_____-_-_-_--_----_----__--____---_-

0.98 ._-_

Canvassed ._ 30) I .^7e 1 C e/l~

r i -- i -- I -- 1.CWrjuur I dn

t.40_ . *.ww _=~vu~rlI

NUREG/CR-6369 A6
Appendix A

II

DEBRIS TRANSPORT RESULTS I

I---

Plant Design:

.Estimate: v I =

Break:

ECCS:

Sprays: I SPR

TREE QUANTIFICATION U. N

Debris Classification Enclosures I Floor

Structures Structures Structures

Above Break Other

Transport

Fraction

| __ __ A. - - - - - - I A _ _ _ _ na^

Srnall Pieces

Large Pieces-Above

r __- 13ni Pc_.1-.s - L,41 YI-,r 4 I -, - & -- I - 9 -

All Large Pieces

All Debris 1 2.842E,01 0.O(

Al Zone-of-Influence

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification

I _..--A A-AA-I-------n----*n*-n0--**- i in_ I. - __A n m AflA] fi - Ao

mQ -11 D; . . .

i ___n i n ! ^iAnC°/ - 7^4 CA1/

nTv Pi %-c-Alinup Lr" ~ . - . I l - I r I _f AO . t An . i A A A A AA I A /

Large Pieces-Below

All Large Pieces

All Debris

I -

RELATIVE CONTRIBUTIONS 4

_ .

- I

Debris Classification

- . _-.

0_11 In.-_ 01IJ=Iur I Ic, U . * . : _ I nn n.n, I .-nA-lfl/

T f___ n.- -n- A ns,

L..i;U r lt e s -r I -. . . , . 1 -: 1- - v -_ - _ . - - , t I

I T - -n_ ------ D-n-1 I I cLarVL1U-Ci0 0_ | / In, 1 to1nn nn , n i ' , m _ _ .- - 1 . - . FA 11 T ___- I 1-.w L,= Y'u, u I , . - - - - - -

Debris Transport Fractions

C

0

U

(U

U.

II I

Small Debris Large Above Large Below All Large Debris All Debris Al Zone-ofGrabngs Gratings Influence

I

A-69 NUREG/CR-63 6 9
Appendix A

LOCA Type 1 Debris Oasificado Blution A f ErErosn and Wasbdown Drywell Floor Pol| Path| | Lo .1 DsrBlodonAfr 

FrtOUI Fna oIto

Advected to Vents 

MARKI I 95SEf Vents 0.89

Enclosures 

UPPE R BOUND EI-00 Enclosures 0.0 ------ - ------------------------------ ___-- 2 0.0E+0--lsu

MSL BREAK 

Watebome 3 0.000E+00 Vents

DryweU Floor - -. 00 NOT-THROTTLED ooo -Sediment 4 0.000E+00 Floor

NO SPRAYS 

0.00

Waterborne 0.000E+00 Venb FIBROUS INSUJLATION 

- --------- et

Condensate Drainage I

Structures-Above 

Som1l 0.E0 Pieces-r Adhees ' 0.0 --0.22 I. ------------- _ 7- .000E+0 Structres-Above

Waterborne 2 6.600 Vents

I '100

RecirulatiFloor

0.0 Se_________Im 2 0.000E+00 Floor

-0.00

0.03 ------------------ - ----------------- 1 0.000E+00 StructuresBreak

Waterborne 24 1.760E-03 Vents

Condensate Dra3inag ; eunn 1 .00+0 Floor

Stn~tres-ofif11.00

0.08 [Adheres 13 154-2 Strueftnu Other

Waterborne _ 4 9.000E-03 Vents

Recirculation Flow

StructuresBreak 12 - t 5 0.000E+00 Floor

r6.a StructuresBreak

0.00

Waterbome 27 0.000E+00 Vents

Condensate Drainage I

03 :0.00 --- -Sedinent 2B 0.00E+00 Floor

St c tu res-Other -- - - - -- - - - * 0.00

MSL Break 0.70 |Adheres 2_ 9 2.20E-01 Structures{Other 1.00 Advected to Vena1ette

1.00N20 

L reB low E Closures ----------------------------------------------- 8.000E2Venb

Enclosures 0.08 Waterbome 22 0.Q00E1+00 Venbs

,Drywell Floor

°0.°° -------- -------- -------- ----- or I 0.00

jWatebore 24 0.000E+00 Vents

| ~Recirculation Flow |

iSI= h---------ent_______,-2 0.000E+00 Floor 0.00tre-3,a Idee_______________ 6 0QO+0 Srcwsra

Waterotme 27 0.QOOE+00 Vents

__curs-je lSedirnent 28 0.OE0 Flo 0.00ders_________________2 0.000E+00 FlooctreOtr

Qavse 40 

4.000E-01 Sh-uctures/Floor

NUREG/CR-6369 A-70
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK I

Estimate: UPPER BOUND FIBROUS INSULATION

Break: SL BREAK|

ECCS: NOT THRO

Sprays: NOSPRAYS

TREE QUANTIFICATION

Debris Classification Vents Enclosures Floor Above Brea Other Fraction

Above Break Other Fraction

Small Pieces 2.042E-01 0.000E+00 0.000E+00 0.OOOE+00 O.000E+00 1.584E-02 0.9280

Large Pieces-Above 9.OOOE-03 0 0.OOOE+00 0 6.600E-02 2.250E-01 0.0300

Large Pieces-Below 8.OOOE-02 0.OOOE+00 0.00OE+00 0 0.OOOE+00 O.OOOE+00 1.0000

All Large Pieces 8.900E-02 O.OOOE+00 0.000E+00 0 6.600E-02 2.250E-01 0.2342

All Debris 2.932E-01 0.000E+00 0.000E+00 0.000E+00 6.600E-02 248-1 0.4886

All Zone-of-Influenc 0.2932

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification Vents Enclosures Floor Structures Structures

Above Break Other

Small Pieces 92.80% 0.00% 0.00% 0.00% 0.00% 7.20%

Large Pieces-Above 3.00% 0% 0.00% 0% 22.00% 75.00%

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00% 0,00%

All Large Pieces 23.42% 0.00% 0.00% 0% 17.37% 59.21%

All Debris 48.86% 0.00% 0.00% 0.00% 11.00% 4

RELATIVE CONTRIBUTIONS (Verti

Debris Classification Vents Enclosures Floor AbovStructure s SB

Above Other

Small Pieces 69.64% N/A N/A N/A 0.00% 6.58%

Large Pieces-Above 3.07% N/A N/A N/A 100.00%

Large Pieces-Below 27.29% N/A N/A N/A 0.00% 0.00%

All Large Pieces 30.36% N/A N/A N/A 100.00% 93.42%

Debris Transport Fractions

1.250

1.000

C 0.750

LL0.500

0.250

0.000

Small Debris Large Above Large Below All Large Debris All Debris Al Zone-ofGratings Grafings Influence

A-71 A-71N'UREG/CR-6369
Appendix A

LOCA Type Debris Clasalficatio Distribution After ErPoatdhsbonDywUFoo ol I rcin ia Lcto

I lowdown I rso n ~bom rwl lo olINO. FrcinI ialLato

Advected to Vents I I.958E-01 Venbs

MARK I

UPPER BOUND

MSL BREAK

NOT THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

Snall Pieces

10.22

-losures 2 f-0.000E+00 Enclosures

Waterborne 3 0.000E+00 Vents ...________ ________ I I _

II.00

Drywell Floor

---- - - - - - -- - - - - - - - ----

0.00 Igedtment 4 0.000E+00 Floor

0.00

Waterborne 5 0.000E+00 Vents

fSedi en___t------ _____E_00 Floor ,!Sediment 6 0.000E+00 Floor

Condensate Drainage

Structures-Above _

0.00 iAdheres

0.00

7 0.000E+00 Stractues-Above

0.90 ___________

Waterbome 8 6.600E-03 Vents

1.00

Recirculation Flow

1.00 'Sedinent

Strutures-Break 0.00

0.03 Adheres

0.00

t1 9 0.000E+00 I Floor

10 0.000E+00 Structures-Break ___________

Waterborne I1 1.760E-02 Vents

1.00

Sprays/Condensate

1.00 iSediment

StrIctures-ther 0.00

0.0 ,Adheres

.1 120.000E10 j Floor

13 0.000E+00 Structure&Other

Stractures-Break

0.25

Large-Above

0.30

,Structures Other

0.75

:____________________________________.

0.00

Waterbome 14 9.000E-03 Vents

1.00

Recirculation Flow

012 Sediment 15 0.000E+00 Floor

0.00

Adheres 16 6.600E-02 Structures-Break

0.88

WaterTbome 17 4.500E-03 Vents

1.00

Sprays/Condensate

0.02 Sediment 18 0.000E+00 Floor

Adheres 19 2.205E-01 Structures-Other

MSL Break

1.00

0.98

Advected to Vent 20 8.000E-02 Vents

n1.00 c___ 21 0.000E+00 Enclosures I __ D_]

R e-tselow i0.00

0.08 F

!1wwel Floor

22 O.OOOE+00 Vents Waterborne --- I.I Il i I.00

:0.00 'Sediment 23 0.000E+00 Floor

0.00 1 _ _ _ _ _ _ _ ___

0.00

Waterborne 24 0.O00E+00 Vent&

__1 

ISediment 

_____ __1 

25 0.OOOE+00 

1____

Floor --------------- _.

Recirculation Flow

I 1.00 --- Strucsures-Bresk

0.00 2&deres

0.00

_________

26 0.000E+00 Struotues-Break

.__________. __ . 0.00

Waterbome 27 0.OOOE+00 Vents

,i jl.00

Sprays/Condensate I

iO.02 -- Sediuent

IStructures-Other i 0.00

0.00 °Adheres

_ 28 0.OOOE+00_I Floor

29 O OOOE+00 Strcs-Other

__________. 0.98

30 4.000E-01 Structures/Floor Canvassed _-- I-- nsn Tn-i I F~r.4)n

NUREG/CR-6369

A-72
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: ARK

Estimate: UPPER BOUND FIBROUS INSULATION

Break: WL BREAK

ECCS:NOT

Sprays: SPRAYS OPERATED

TREE QUANTIFICATION

Debris Classification Vents Enclosures Floor Arove Brea Other Fraction Above Break Other Fraction

Small Pieces 2.200E-01 O.OOOE+00 0.00OE.OOOE+O00 E+00 O. 00 0 0.OOOE+O0 1.0000

Large Pieces-Above 1.350E-02 0 O.OOOE+00 0 6.600E-02 2.205E-01 0.0450

Large Pieces-Below 8.OOOE-02 O.OOOE+00 O.OOOE+00 0 0.OOOE+00 0.1OOOE+00 1.0000

AR Large Pieces 9.350E-02_ O.OOOE+00 IO.OOOE+00 O0 6.600E-020 2.205E-01 Ad0.2461

All Debris 3.135E-01 OOE+0O.OOOE+00 O.OOO1E+00 6.600E-02 2.0E0 .5225

All Zone-of-Inlence .3135

Debris Classification Vents Enclosures Floor Structures Structur Above Break Oer

Small Pieces 100.00% 0.00% 0.00% 0.00% 0.00% 0.00%

Large Pieces-Above 4.50% 0% 0,00% 0% 22.00% 73.50%

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00% 0

AU Large Pieces 24.61% 0.00% 0.00% 0% 17.37% 58.03%

All Debris 52.25% 0.00% 0.00% 0.00% 11.00% 36.75%

RELATIVE CONTRIBUTIONS (Vertical)

IStructures Structures Structures

Debris Classification Vents Enclosures Floor Abves Brea Otru

IAbove Break Ote

Smnall Pieces 70.18% N/A N/A N/A 0.00% 0.00

Large Pieces-Above 4.31% N/A N/A N/A 100.00% 100.00%

Large Pieces-Below 25.52% N/A N/A N/A 0.00% 0.0

All Large Pieces 29.82% N/A N/A N/A 100.00% 100.

Debris Transport Fractions

1.250 -

1.000

r- 0.750-

ii 0.500 -

0.250

0.000

Small Debris Large Above Large Below All Large Debris All Debris All Zone-ofGrabings Gratings Influence

A-73 A-73 NUREG/CR-6369
Appendix A

A.4.1.2 Recirculation Line Break

This section contains upper bound estimate logic charts for Mark I recirculation line break scenarios.
Appendix A

LOCA Type Debris Casifeado Distribution After Erosion and Wasbdown Drywell Floor Pool | I Fraction | Final Locatlon

II Blowdown . INo.

Advected to Vents I O.OOOE+00 Ventb

MARK I

UPPER BOUND

RL BREAK

ECCS THROTTLED

NO SPRAYS

FIBROUS INSULATION

Snall Pieces

0.22

l3ge-Above

0.30

lo-o --------

iEnclosures 2 0.OOOE+00 Enclosures I--__ __ __ . __ __ __ _ __ __ __ _ __ __ __ _ __ __ ___

'000

* Waterborne 3 2.200E-O1 Vents

* *1.00

,Drywell Floor

1.00 iSediFnlt 4 0.OOOE+O0 Floor

_-------- ___-

0.00

Waterborne 5 0.OOOE+00 Vents

'1.00

Condensate Drainage 1

Sedinent 6 0.OOOE+00 Floor

tructures-Above 0 .00,

LAdheres 7 0.OOOE+O0 Structures-Above

0.90

Waterborne 8 0.000E+00 Vents

'1.00

Recoulation Flow i

L10 LSeuret 9 0.000E+00 Floor

,Strucftures-Break 0 .00 r 0.00 10 0.000E+00 Structures-Break '0.00 Adheres I ,.____________ ___________ _______

0.00

Waterborne 11 0.000E+00 Vents

Condensate Drainage I

j.10 iSediment 12 O.OOOE+00 Floor

Structures-Other ' 0.00

IAdh 13 O.OOOE+00 Structures-Other 0.00 t _ _ __ _ __ _ __ . __ _ __ _ __ _ _ __ _

0.90

Waterborne 14 3.600E-02 Vents

1.00

Recirculation Flow -

0.12 iSediment 15 0.0OE+00 Floor

Structures.-Break ________ ___

1.00 Adheres 16 2.640E-01 Structures-Break

Waterbome 17 0.OOOE+00 Vents

Ir-------------

(Condensate Drainage i

--- -- jSedinnent 18 0.000E+00 Floor

|Structures-Other 0 o.00

0.00 *Adheres 19 O.OOOE+00 Structures-Otber

1I.00

Advected to Vent 20 8.0OOE-02 Vents

L1.00

Enclosures 21 O.OOOE+00 Enclosures

R.L Break

.00

. _ .

I-arge-Below -------__

0.08

'Drywell Floor

Waterborne 22 O.OOOE+00 Vents - ----- - i 1.00

1-1 -- -- -- -- -- - - - - - - - -- -- -- -- -- -

10.00 23 0.000oE+00 Floor

0.00

Waterbome 24 0.000E+00 Vents

11.00

ISedirent 25 0.OOOE+00 Floor

Recirculation Flow

[ r-----------________. A1.00

LStrufures-Break

lo-oo lAdheres______

0.00

26 O.OOOE+OO Structures-Break

0.00

Waterborne 27 0.OOOE+00 Vents

I 1.00 I Condensate Drainage I

II lo.o -Sedirnent

jStructures-Other t 0.00 - ----

0.00 Wheres

--------------------------- _

t 28 0.000E+00 Floor .__________

29 0.000E+00 Structures-Other

1.00 .____ _____

Canvassed 30 4.000E-01 structures'Floor

A AA T-1 1 oAAAOO

NUREG/CR-6369

A-76
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK I

Estimate: UPPER BOUND FIBROUS INSULATION

Break: RLBREAK

ECCS:ECCSTHRO,

Sprays: NO SPRAYS

TREE QUANTIFICATION

C Structures Structures Structures Transport

Debris Classification Vents Enclosures Floor Above Break Other Fraction

Small Pieces 2.200E-OI 0.OOOE+00 O.OOOE+00 0.0001E+00 O.OOOE+00 O.OOOE+00 1.0000

Large Pieces-Above 3.600E-02 0 0.OOOE+00 0 2.640E-01

Large Pieces-Below

All Large Pieces

All Debris

All Zone-of-Influence

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

RELATIVE CONTRIBUTIONS i

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces ________________ I I h

Debris Transport Fractions

1.250

1.000 _

0

U.

0.750 -

0.500 4--

0.250-

0.000

Srnall Debris Large Above Large Below All Large Debris

Gratings Gratings

All Debris All Zone-ofInfluence

A-77 NUREG/CR-6369
Appendix A

LOA Ip DbsC1asifieadoJ Distribution After I abo P.t- I I

C Blod I Eroowon and Wasbdownl Drywell Floor Pool INo. Fraction FInal Location

Advected in vert I I I MARK I

UPPER BOUND

RL BREAK

ECCS THROTMED

SPRAYS OPERATED

FIBROUS INSULATION

Snial Pieces

10.22

1=7 nn --- - - ------------- - ---------------- L u.uA------ )E+00 lU.W

I Enclosures A - --- --

Vents

UMJIJ~+O_ .n~su~ i~~~~~ ~~~ ___________________________ OUw00 E. closures I- - - - - - - - - - -- 1 ---- - -- - - --- - - - - -

IDrywell Floor

Waterbcore 3 2.2u0E.01 Vents r. __ _ _ _ .

I .MW

|I 00

IOw

0.00

4 0.000 +00 Floor

Waterborne

I .

Cor~lensate Drainage 100

,0.10 ISedient

Sotiow s-Above -

0.00 --- 2.0 --------- Adheres

5 0.000E+00 Vents

6 0.0w0E+00 Roor 0.000E400 F1--- 4

7 0.wo0E+00 S uturwf-AF-v

n -.- -- -. _-_-- I u.YU

Waterborne

r-----------_____-

'1.00

Reciculation Flow 1 -.- 5

,I.w0 'Sedi nnt Stnctures-Break j

0.0 - - Adheres

8

9

0.0000E+00 Vents

0wwF.+00 M. _ i ( 4Y

In nn--n

n nn -~~~~~~~~~ -I v u.wurt I ruCtUrcs brea)( - ...- -...

u.w

I Waterbome

al].00 Sprays/Condensate 1

"1.00 iSednent

L~ ---- I0.00

0.00 fAdheres

II 0-O1.0wE0 V-n

12 0.00E+00 Floor

13 0.wwE+w Stnr,"srhv

Stctus-Break

1.00

Lar-bov

0.30

I Sructres-Other

0.00

Advected to Vent

...5 -- ----------- ...

Watesbome 14 3.600E-02 Vents

1.00

Recirculation Flow

0.12 ,Sediment I 5 0.wWE+00 Floor 0.12----------_ lo

OAdheres 16 2.640E-01 Structures-Break

0.88

,WLero__ 17 0.wwOE+wo Vents

Sprays/Condensate 1

10-02 Sedinnt 18 0.000E+00 Floor

-- 0.00

RL Break LAdhere -- 19 0OOwwE+w Structuee

1.00 -u.o

20 R l~lll VA"

.1.00

~Enclosures --------------------- Enclosures---- Large-Below

0.08

ll'Drywell Floor

Waterbome 22 O.ww0E+OO Venbt

a--n___ _.____ .__ .______ I______ W -. II

I A n -

.UV

is 23 O.OoOE+00 Floo

me 24 0.0wOE+00 Vents

25 0.wwOE+00 Floor

I I11.00 I rRecirculadon Flow __ - -- ;1.00 I Sedirent

Stutures-Break . O-w - - ...--- 0.00

0.M !Adheres 26 AO.V4O.+O Rm rtl Ir^eRrL n ------------------------ ---- -- v---- lk

U.A

Waterbome 27 0.000E+00 Venbs

ii F.00 * Sprays/Condensate I *1 I- I _ _ ... II iO.02 I Sediment ed...re

1StructuresIther .

0.00 iAdheres

_________. 28 .w000E+00 Floor

29 O.OOmOEO StruntllrechhAr ...4AV -------------- __-____-I _ . -W

0.90

Canvassed 30 Aonno I cs.>^./n

I.40 - _ _ . . .wIc 'LuoT I lotal I I .(ME4-00 i

NUREG/CR-6369 A-78
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design, MARK I

Estimate: UPPER BOUND FIBROUS INSULATION

Break: RLBREAK

ECCS:ECCS THROTTLE

Sprays: SPRAYS OPERATED

TREE QUANTIFICATION

i Structures Structures Structures Transport Debris Classification Vents Enclosures Floor Above Break Other Fraction

Small Pieces 2.200E-01 O.OOOE+00 0.000E+00 O.OOOE+00 O.OOOE+00 O.OOOE+00 1.0000

Large Pieces-Above 0 0.000E+00 0 2.640E-01 I 0.OOOE+00 I

Large Pieces-Below

All Large Pieces

All Debris

All Zone-of-Influence

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris L i-iRELATIVE CONTRIBUTIONS i

Debris Classification

_ . I A i | . A } I -

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces - I aa -

Debris Transport Fractions

1.250

1.000

0

Uj

U0.750 _-

0.500 +-

0.250 -1--

0.000 4-_ 0.I00 ---- I M I I

Smiall Debris Large Above Large Below All Large Debris

Gratings Gratings

AlI Debris All Zone-ofInfluence

A-79 NUREG/CR-6369
Appendix A

LOCA Type i DiutaibudonAfter f I Path [Debris Classificao Biowdown IErosion and Wasbdown1 Drywell Floor Pool P Fraction I Final Location

.o) _ MARKI

UPPER BOUND

RL BREAK

NOT THROTTLED

NO SPRAYS

FIBROUS INSULATION

:...__:_ _... I VU.W

lEnaclosures I -

0.000E+

I-------------------__------------_-- ilnclsue _______

II',-

II Waterbomne 3

Waterborne 3

iDryweH Floor 11.0w

1.00 Sedim t----------

0.00

Waterboome

Condensate Drainage I

_0.10 ,Sediment

Strmtures-Above I -

0.w0 iAdheres

0.90

Waterborne

Recirculation Flow I

Stncftures-Break I - -. - --__ 0.00 j0.0 iAdheres

4

5

6

Small Pieces

0.22 7

8

9

10

Z.ZOOE..4

0.000134-

0.000E+{

0.OOOE+C

0 OOOE+O

0.OOOE+O(

0.000E+c.

9.000E-~02

----- ------- ---- --- ---- -- . I 0.00 -

Waterborne

Condensate Drainage I sr r 'e010 Sedient

Other -----. ' 0.00 0.00 fAdherea

... - - - - - - - - - - - - - - - - - -

10

11

12

13

14

00 Vents

-00 Enclosures

Vents

Floor

0 Structures-Above

50 Vents

0 Floor

0 Structures-Break

1 Vents

0 Floor

O Structures"Oli'er

Z Vents

FlRoor

Structures-Break

Vents

Floor

IStnictures-Other

_Vents

_Eaclosures

I

I

0.90

Waterborne

.. 9.OE0

I- - 9 0.00

|Sddihente 5 0.000

L...19 0.000

l .ooAbee 16 2.100E

Watetborne | 17 0.000E

1.00

AdvectedetoiVent 2 8 .000E

0.0 Aders

02' 

RL Break

1.00

I

-- - -- - -- - - -- - -- - -- - - ------- _-_-_-_-

0.08 Waterborne

irywelFloor

0.° °°'Sedimlent

i - --- ---- --- ---- --- 0 .

Waterborne

: -1.00 ------

I Recirculation Flow I -

'Structure-Break - L______[A_____s___ 0.00 10.w 0bee

21

22 1

23

24

0.000E+00

0.OOOE+00

0.000E3+00

0.000E+00

Vents

Floor

Venbs

,- -____-__-__-__-__-__-____- __- __- __- __- __- __-____- __- _L0.00 ------

Waterbome

I - -

i C ondessate Drainage

LStct e °°Sediment

0.00 iAdheres

L25 0.000E+00 Floor

26 0.000E+00 Struceues-Break

27 |0.0wE+w Vents

28 0.000E+00 Floor

29 0.OOOE+00 Str cmmres-Osr

30 4.Ow0E-01 Strucmutes oor

-I-------------------------------------

I.W

Canvassed

r IdfI

NTJR GICR 6369A-I 1.000E+00 I

NLTREG/CR-6369 A-80
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK I

Estimate: UPPER BOUND FIBROUS INSULATION

Break: RL BREAK

ECCS: NOT THROTTLE

Sprays: NOSRAYS

TREE QUANTIFICATION

Debris Classification Vents Enclosures Floor Structures Structurea Othes Transport Above Break Other Fraction

Small Pieces 2.200E-01 0.000E+00 0.000E+0f 0.OOOE+00 O.OOOE+00 0.000E+00 1.0000

Large Pieces-Above 9.000E-02 0 0.000E+00 0 2.1OOE-01 0.000E+00 0.3000

Large Pieces-Below 8.OOOE-02 I A Afl .-+ I 0 0.000E+00 I 0.OOOE+00 1.0000

All Large Pieces 1.700E-01

'2 ann;c Al

0 2.100E-01 0.OOOE+001 0.4474

All Debris I FN.4-An I nI I 2MP4-M I 1 ACIRl 0 (MOP4-4 0.6500

All Zone-of-Influence

FINAL DISTRIBUTIONS (Horizontal) 1 1

Debris Classification Vents Enclosures Floor Structures Itructures

Above Break

3tructures

Other

Small Pieces 100.00% 0.00% 0.00% 0.00% 0.00% 0.00%

Large Pieces-Above 30.00% 0% 0.00% 0% 70.00% 0.00%

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00% 0.00%

All Large Pieces 44.74% 0.00% 0.00% 0% 55.26% 0.00%

All Debris 65.00% 0.00% 0.00% 0.00% 35.00% 0.00%

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Structures Structures Structures Above Break Other

Small Pieces 56.41% N/A N/A N/A 0.00% N/A

Large Pieces-Above 23.08% N/A N/A N/A 100.00% N/A

Large Pieces-Below 20.51% N/A N/A N/A 0.00% | N/A

All Large Pieces 43.59% N/A N/A N/A 100.00% N/A

Debris Transport Fractions

1 250 ---

0.0 -

0.750 - 0

U 0.500 ---

0.250 4-

0.000 - WM== i

Small Debris Large Above

Grabngs

Large Below All Large Debris

Gratings

All Debris All Zone-ofInfluence

NUREG/CR-6369 A-81
Appendix A

LOCA Type Debs ClIfcao Distribo After I Erosion and Wasbdown| Dryweli Floor Pool I Na| Fracdon FInal Location

IBlowdown _No.I . Po . _ I _ AdVected to Vents I I 0.00E+00 Vents

MARK I

UPPER BOUND

RL BREAK

NOT THROTLED

SPRAYS OPERATED

FIBROUS INSULATION

Srmal Pieces

10.22

I ----- ---------- -- _ ___

lEncosures 2 Enclosures

I---- ---- ----- ---- ---- ----- ----- ---- ----- ---- ;u.LR

iDrywell Floor

Waterbome 3 2.200E-01 Vents II

I1.00

. t

1.00 iSedinent 4 O.OOOE+00 Floor

0.00

Watertorne 5 0.0wOE+00 Vents

',100 I.

1

Sediment 6 O.000E+00 Floor

Condensate Drainage

,0.10

3tructures-Above i

iAdheres

M.U

7 0.0wOE+00 Strucres-Above ------------ -------- - --- ... ---- - I

0.90

Waterbome 8 O.OO0E+00 Venth

;1.00

Recirculation Flow

r---------------I SrmucRo re ---- - 0.00

0.00 W~heres

_________. 0.wI E+o Floor

10 0.w0E+00 Structures-Break AA -A _ 0.00

Waterborne II 0.w00E+00 Vents

I 1.00

i Sprays/Condensate 1

| 'I g'Sedirnent i '100 L

'Structures-Otber I 0.00

0.00 -.W !Adheres

t 12 f 0.000E+00 Floor

13 0.000E+00 Structures-Other

Structures-Break

1.00

Large-Above

).30 I

istructurcs-er

0.00

0.00

Waterbomne 14 9.0OOE-02 Vents

1.00

Recirculation Flow

0.30 ,Sedirnent 15 0.OOOE+00 Floor

0.00

Adheres 16 2.100E-01 Strucnares-Break

0.70

Wateoorne 17 0.OOOE+00 Vents

:1.00

Sprays/Condensate I

;0.02 Sedinent 18 O.O OE+00 Floor

"Adheres 19 0.OOOE+00 Structures-Other A-..._r_-__________ RL Break

1.00

0.98

Advected to Vent 20 8.w0OE-02 Vents

1.00

Enclosures ____________________________ 21 I-0.000E+00 Enclosures I-- -o1--w LaU6w 0.00

0.08

bDrywell Floor

Waterborne 22 O.OOOE+0 Vents l --------------- 'I .00

--- -- -- -- -- -- -- -- _- _ __-_-- _- __-_-!Semett 23 0.000E+00 Floor

0.00

Waterbomne 24 O.OOOE+00 Vents

'TSedirnent 25 O.OOOE+00 Floor

Recirculation Flow

1.00 .Structures-.rea. . .

20.00 adhrres

0.00

26 0.OOOE+00 Strictures-Break ------------------- ._________--

0.00

Waterborne 27 O.OOE+00 Vents

I '1.00 I I Iw

I Sprays/Condensate I

1 02 --. Seditnent

iStructures-Other 0.00

0.00 -Adheres

28_______Flo

t----- _____, 2 .OE+OO R Foor _

29 0.000E+00 Structures-Other --------------------- __________--

0.98

Canvassed 50(~ dCtfF..f StrucFloor A -- VU i I 0.40 To1 I 1 Annrzf

NUREGICR-6369 A-82
Appendix A

DEBRIS TRANSPORT RESULTS|

Plant Design: MARK I

Estimate: UPPER BOUND FIBROUS INSULATION

Break: RL BREAK

ECCS: NOT THRO¶TLED

SPRAYS OPERATED

TREE QUANTIFICATION

DebisClasiictio Vnts Enloure Foo Structures Structures Structures Transport

Debris Classification Vents Enclosur Floor Above Break Other Fraction

Small Pieces 2.200E-01 0.OOOE+00 0.000E+00 0.000E+00 0.OOOE+00 0.OOOE+00 1.0000

Large Pieces-Above 9.000E-02 0 0.OOOE+00 0 2.100E-01 0.000E+00 03000

0.OO E 0 -- - ---- ULarge Pieces-Below 8.OOOE-02 I 0.OOOE+00 I 0.OOOE+00 0 0.000E+00 OU

All Large Pieces 1.700E-01 I0.000E+00[

_ _

0 2.IOOE-01

2.IOOE-0l

0.

I.0000

0.4474

0.6500 All Debris 'oAnF n1

All Zone-of-Influence

FINAL DISTRIBUTIONS (Horizontal) . -

Debris Classification Vents Enclosures Floor Structuresl Structures Structures

Above I Break I Other

Small Pieces 100.00% 0.00% 0.00% 0.00% 0.00% 0.00%

Large Pieces-Above 30.00% 0% 0.00% 0% 70.00% 0.00%

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00% 0.00%

All Large Pieces 44.74% 0.00% 0.00% 0% 55.26% 0.00%

All Debris 65.00% 0.00% 0.00% 0.00% 35.00% 0.00%

REIATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Above Break Other

Small Pieces 56.41% N/A N/A N/A 0.00% N/A

Large Pieces-Above 23.08% N/A N/A N/A 100.00% N/A

Large Pieces-Below 20.51% N/A N/A N/A 0.00% N/A

All Large Pieces 43.59% N/A N/A N/A 100.00% N/A

Debris Transport Fractions

1.250

1.000

C

U.

0.750 l0.500 -1--

0.250

0.000

I _ ~

Small Debris Large Above

Gratings

I _

Large Below All Large Debns

Gratings

All Debris All Zone-ofInfluence

A-83 NUREG/CR-6369
Appendix A

A.4.2 Mark II

This section contains the upper bound estimate logic charts for the Mark II design.

A.4.2.1 Main Steam Line Break

The upper bound estimate logic charts for the main steam line breaks are presented here, then the charts

for the recirculation line breaks are presented in Section A.4.2.2.

A-85 NUREGICR-6369
Appendix A

____ _r __p___ _ |-I - _ _ _ LOCA Type IDebris Classificadon DII~Btlowdo A Ie Eroslon and Wasbdown forP o Nrwl . Blwon - . Frat - FI alLctn

-1-e - vensM I 1-9IqRF.fl VenMARK 11

UPPER BOUND

MSL BREAK

ECCS THROTTLED

NO SPRAYS

FIBROUS INSULATION

0.890. E--,_ 1 Enclosu

en -- - -- - -- - -- - -- - -- - - -- - -- - -- -- loue

u.w

Waterborne 3 0.000E+00 ...________________. -

Drvwell Floor

.OO

i

3.03 ISedinient 4 6.600F-03 PI-,

l.w0

Waterbome 5 0.OOOE+00 Vents

10.00

_______________. et

iSediment 6 0.000E+00 Floor

Condensate Drainage

0.10

Strixtures-Above i

3.0w -Adhieres Small Pieces

0.22

1.00

7 OO.E+00 Structures-Above -------------------------------------- _ 0.90

Waterborne 8 0.000E+00 Vent

iO.00

Condensate Drainage I

0.10 ISedmient

Strictures-Break 1.00

0.02 Adheres

.________ -.-- _ Flo

4 in 3.960E-03% Sh^.W^hl"YlRrPAL -- i 4--_ I . I , .

0.90

Waterbome II 0.000E+00 Vents

;0.00

Condensate Drainage |

0.10 ISeduonen

Strctu thet I 1.00

0.06 Adheres

12 I .320E-03 Floor

13 1.188F-02 Struchxres Otber

Statrucs-Break

0.25

Large-Above

0.30

Struture's-otber

0.75

Advected to Vent

0.90

Waterbome 14 0.000E+00 Vents

:0.00

Condensate Drainage I

0.00 tSedinient 15 0.OOOE+00 Floor

1.00

tAdheres 16 7.500E-02 Stenctures-Break

1.00

Waterbome 17 0.w00E+00 Vents

Condensate Drainagei

10.00 ... *Sedjment 18 0.w00E+00 Floor

LAdhees 19 2.250E-01 Structures-Other MSL Break

1.00

1.00

20 8.OvE-02 Vents

Enclosures 

....W _I______________ 21 00E+0 Enclosures Large-Below

0.08 V.L)

Waterboroe 22 O.O.E+-0 Vents

!Drywell Floor

- __ __--_- _--_--__ -. -- -

i0.00

! AA - -- - - - - -- - - - - -- - - - - ;0.00 23 0.000E+00 Floor

ne 24 0.000E+00 Vents

25 O.000E+00 Floor

10.00

Condensate Drainage I

i0.00 i Sedfimtn

Slctures-Break i ___

0.00 !Adheres 76 O wwE+w qtmfire Bk ..., ___ --------------- -- i _-_-------_---------- I II

1.00

Waterbome 27 0 .000E+O0 Vents

1 10.00

i Condensate Drainage I

lo.0w 0 Sedirrit

StnuwOther I I .0

0.00 iAdhees

t 28 O.wOOE+00 Floor

79 Ol(wOE+00(V S^.ru^,hhPr

-~ I...., - -a I I I.W Canvassed iA I .A NVA tfl Chanhsr/7lAA_

n n _. . { .- I aues Ploor

NUREG/CR-6369 A-86
Appendix A

DEBRIS TRANSPORT RESULTS I

Plant Design:

Estimate:

Break.

ECCS:

TREE QUANTLFIC.

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

All Zone-of-Influence

FINAL DISTRIBUTTI

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

RELATIVE CONTI

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

_MARK II

NISLBRA|

_ECCS TRTL

.NO SPRAYS|

A ITON

. et nlsue lo Structures Structures Structures Transport

V Above Break Other Fraction

1.958E-01 O.OOOE+00 8.360E-03 O.OOOE+00 3.960E-03 1.188E-02 0.8900

O.OOOE+00 0 O.OOOE+00 0 7.500E-02 2.250E-01 0.0000

8.000E-02 O.OOOE+00 O.OOOE+00 0 O.OOOE+00 O.OOOE+00 1.0000

8.OOOE-02 0.000E+00 O.OOOE+00 0 7.500E-02 2.250E-01 0.2105

2.758E-01 O.OOOE+00 8. 60E-03 OOOOE+00 7.896E-02 2.369E-01 0.4597

0.2758

BONS (Horizontal)

Vents Enclosures Floor Above Brea Otr _Above Break Ote

89.00% 0.00% 3.800% N..0% 5.02%

0.00% 0% 0.00% 0% 25.00% 94.98%

100.00% 0.00% 0.00% N0% 0.00% 0.00%

21.05% N/A 0.00% 0N 9.98% 594.9%

_ 45.97% 0.00% 1.39% 0.00% 13.16% .8

R 1BUTIONS lVrtical)

_Structures Structuresre

Vents Enclosures Floor Above Break _ he

_ 70.99% N/A 100.00% 7N/A 5.02% 502

_0.00% N/A 0.00% N/A 94.98% 9.8

_ _29.01% N/A E0. 00% N/A 0.00% 0%

_29.01% N/A I0.00% N/A 94.98% 94.98%

Debris Transport Fractions

1.250

1.000

0

Z

(U

U0.750 _-

0.500 -

0.250 -_-

0.000 -

Small DebHs Large Above Large Below All Large Debris

Gratngs Grafings

All Debris All Zone-ofInfluence

A-87 A-87 NUREG/CR-6369
Appendix A

LOCAy___________ sif________ strbuon_ AftrErosinand_________Drywe__FlooroolPahactio___na__ocPato

LIC Tye Dbi ssfed ~ Bldown Ir EIeo ndWsdw lo oo Nrwi . Fato inlLct

BlowdoInLNo

Aavecer to vents I I.95SE-01 Vents

MARK 11

UPPER BOUND

MSL BREAK

ECCS THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

Snull Pieces

10.22

0.89 _ Ecosres c 2 , _0 000 E+00 Enc ________O. losumres

0.MU

Waterborre 3 6.600E-03 Vents .4 4 5

I1.00

Dryvell _ , _ Floor I

0.03 iSediment

0.00

Waterborn

11.00

Condensate Drainage I

lo 10 nSediseot

Structures-Above 0 00 -.

0.00 -Adheres

4 0.000E+00 Fnnor

ne 5 0.000E+00 Vents

- 6 0.OO0E+00 Floor

7 0.000E+00 Sloctures-Above ____________________ -...__ -_-----------

0.90

Waterbome 8 4.400E-03 Venth

1.00

Sprays/Condensate

1.00 'Sedinent

Structures-Break I_0.00

0.02 iAdheres

-. 191 0.000E+00 Floor

10 0.000E+00 Structures-Break t_____________________________________

0.00

Waterborne 11 1.320E-02 Vents

1.00

Sprays/Condensate

1.00 Sedirnent

Structures-Other 0.00

0.06 !Adheres

___ 12 0.OOOE+00 f Floor

13 0.OOOE+00 Structures-Other

Structures-Break

0.25

Large-Above

0.30

,StructuresOtber

0.75

O. 00 -- - ---------- __-- - -_-.--- - 0.00

Waterbome 14 t.500E-03 Vents

1.00

Sprays/Condensate

0.02 ISedinent 15 0.000E+00 Floor

Adheres 16 7.350E-02 Structures-Break

0.98

Waterbome 17 4.500E-03 Vents

1.00

Sprays/Condensate

0.02 Sedim t 18 0.OOOE+00 Floor

0.00 ---------- ____

_Adheres 19 2.205E-01 Structures-Other

MSL Break

1.00

0.98

Advected to Vent 20 8.000E-02 Vents I1.00

Enclosures -21- 0.000E400 Enclosures

Large- Be low _ _o

0.08

!Drywell Floor

Waterbome 22 O.OOOE+00 Vents __________________- I __

---- _ _ _ _ _ _ l l

i0.00

'----------------------------------4

10.00 !Sedinent 23 I O.OOOE+00 Floor

1.00

Waterborne 24 O.OOOE+00 Vents

10.10

I~fSedimsent 25 0.000E3+00 Floor

Sprays/Condensate

'0.02

Stictures-Break I

0.00 - L ----0.90

26 0.000E+00 Structures-Break s_---_---__---_-------------------------

0.98

Wateibome 27 o.oooE+00 Vents

'0.10 i Sprays/Condensate I

0.02 - Sedi-ient

StsOther | 0.90

0.00 WAdheres

{ 28 O.OOoE+00 ] Floor

29 0.oooE+00 Structures-Other -- ___-----------___----------__-_ 0.98

Canvassed 30 4.OOOE-01 Structures/Floor ._ _ _ I 

n 44 -- I I, IDWY

NUREG/CR-6369 A-88
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK II

Estimate: UPPER BOUND FIBROUS INSULATION

Break: ISL BREAK

ECCS:ECCS THRO

Sprays: SPRAYS OPERATED

TREE QUANTIFICATION

Debris Classification Vents Enclosures Floor Structures Structures Structures Transport Above Break Other Fraction

Smnall Pieces 2.200E-01 I O.OOOE+00 I 0.00013N0 O.0OOE+0.OOOE+00 O.OOOE+00 I 1.0000 .9-

Large Pieces-Above I 0 °O.OOOE+00 0 7.350E-02 I 2.205E-01 I 0.0200

Large Pieces-Below I O.OOOE+00

_O O.OOE+00O

0

0

0

All Large Pieces

I 1.0000

_0.2263

.0.5100 __

All Debris 3

All Zone-of-Influence

FINAL DISTRIBUTIONS (Horizontal) . .

Debris Classification Vents Enclosures Floor Structures Structures Structures

Above I Break I Other

Smnall Pieces 100.00% 0.00% 0.00% 0.00% 0.00% 0.00%

Large Pieces-Above 2.00% 0% 0.00% 0% 24.50% 73.50%

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00% 0.00%

Al Large Pieces 22.63% 0.00% 0.00% 0% 19.34% 58.03%

All Debris 51.00% 0.00% 0.00% 0.00% 12.25% 36.75%

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Abves Brea Other lAbove lBreak lOther

Snmall Pieces 71.90% N/A N/A N/A 0.00% 0.00%

Large Pieces-Above 1.96% N/A N/A N/A 100.00% 100.00%

Large Pieces-Below 26.14% N/A N/A N/A I 0.00% 0.00%

All Large Pieces 28.10% N/A N/A N/A I 100.00% I 100.00%

Debris Transport Fractions

1.250 1

1.0001

0.750 - 0

to

(U 0.500 4--

0.250 +-

0.000-

Small Debri

III

is Large Above Large Below Al Large Debris

Gratings Grafings

Al Debris All Zone-ofInfluence

A-89 NUREG/CR-6369
Appendix A

[.0

LOCA Type I~ebri Classlficsdioni BlstIirosionAane Washdown Drywell Floor Po

Advected to Vents

IMARXK U Roa

UPPER BOUND

MSL BREAK

NOT THROTTLED

NO SPRAYS

FIBROUS INSULATION

Enclosures

nn --------------- - ------------.-.

WaterCoDn

Dryuwell Floor

0 03

0.0000

Watlbomne

r---------------

Conderlsate Drainage I

1. --- --- 1Sediret

Stnfues-Above i oT-------- Y(;T ------- -IAdhe.e Srnall Pieces

10.22 0.90 -- -- ------ -- - -- -- -- -- -

Waterbomne

1.00

Recirculanion Flow

0.10O Sediment

StructuvsBreak s ---- e

0.00

0.02 Adheres

0.00_

Waterbome

1.00

0.10 Svnn Structures{_)ther L____ _ -_-________-

.Ov Aene:

O.,^O

Waterbome

0..00

Recirculation Flow 10

0.12 Sediment Stnxtws-Break -----------------

0.5 dh=0.00

0.75 OAd8eres

Waterbome

1.00

Advected to Vent

Pa l Fnaction I Final Location

No.

_ - 1.95SE41 Vents

2 O.OOOE+00 Encloss

3 6.600E-03 Vents

4 O.OOOE+00 Floor

5 0.000E+0O Vents

6 0.000E+00 Floor

.7 O.OOE+OO Structurs-Above

8 4.400E-03 Vens

9 0.OOOE+00 Floor

10 0.000E+00 Structures-Break

_ 11.320E-03 Vents

12 O.OOOE+00 Floor

13 1.188E-02 Strnctres-Other

14 9.000E-03 Vents

15 O.OOOE+00 Floor

16 6.600E-02 Structues-Break

17 OA.XOE+300 Vents

18 0.OOOE+00 Floor

I 9 2.250E-01 Structures-Other

20 8,SOE02 Vents

21 0.OOOE+00 Enclosures

22 O.OOOE+00 Vents

23 0.OOOE+00 Floor

24 0.OOOE+00 Vents

25 0.OOOE+00 Floor

26 0.000E+00 Structues-Break

27 O.OOOE+00 Vents

28 0.OOOE+00 Floor

29 O.OOOE+OO Structures-Other

30 4.000E-01 Structues/Floor

:E^I I t,007 0

I

IL Break

0

II ,^

I us Large-Below

0.08

lovw ---- _------------------_-----_--------------I

Waterbome

i r---------______- !Dryvel Floor 1

100o sedjmnent

0.00

I Waterbome

Recirculation Flow 0

I- --- LS~oresB --- --------- ~ -- L w10 a 0 .00 1Sedimnent

10.00 lAdheres ! A-A---------- ----------------- _------ n1 ,^^ ----- I__

Waterbomne

Ij 1. 0 0 Condensate Drinage 1

I 0.0 -Sedinent

aStrwctures Other i O -w 0.00 . Adheres

A----------- ----------- _____

I n --------------------- I .w Canvassed n an U . QI

NUREG/CR-6369 A-90
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK II

Estimate: UPPER BOUND FIBROUS INSULATION

Break:-

ECCS: NOT THRO1ILED

Sprays:NO SPRAYS|

TREE QUANTIFICATION

Structures Structures Structures Transport

Debris Classification Vents Enclosure Floor Aoe Bra Otr

Above Break Other Fraction

Srnall Pieces 2.08%1 E-0 0.00% 0.000%+0 0.00%E+ 0.00%E+00 5.188E-02 0.9460

Large Pieces-Above 9.00%E-03 0 0.00E+00 0 6.600%02 2.250E-01 0.0300

Large Pieces-Below 8.1 E-02 0. E+0.00 00%0.00% 0 . 00 E+00 1.0000

All Large Pieces 8.900E-02 4 .2% 0E+00 0.000E+00 0 6.600E-02 2.250E-01 0.2342

All Debris 2.971E-2 0.000E+00 .E+00 0.000%+00 6.600E-02 2.369%-01 0.4952

RENLADITIVECOTRBTIONS (Verzotal)

Debris Classification Vents Enclosures Floor Alves Break Othru Above Break Ote

Srmall Pieces 94.60% 0.00% 0.00% 0.00% 5.02%

Large Pieces-Above 3.00% 0% 0.00% 0% 22.00% 9

Large Pieces-Below 100.00% 0.00% NA N 0.00% 0.00%

All Large Pieces 23.42% N/A 0.00% 0% 17.37%

All Debris 49.52% 0.00° / 0.00% 0.00% 11.00% 3.8

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Trsor StFractionsSr Above Break other

Srnall Pieces 70.05% N/A NlA N/A 0.00% 502

Large Pieces-Above 3.03% N/A N/A N/A 100.00% 948

Large Pieces-Below 26.93% N/A, N/A N/A 0.00% .%

All Large Pieces + 29.95% N/A I N/A N/A 100.00%8

Debris Transport Fractions

1.250 -

1.000 -

O 0.750 -

LA. 0.500

0.250

0.000

Small Debris Large Above Large Below All Large Debris All Debris Al Zone-ofGrabngs Gratings Influence

A-91 NUREG/CR-6369
Appendix A

LOCA Type Debris Clusificadoo D Blowdown A Erosion and Washdown Drywell Floor Pool Frction Fnal Location

Advected to Vents I I.95SE-01 Vents

MARK II

UPPER BOUND

MSL BREAK

NOT THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

Srrll Pieces

0.22

3.89

Enclosurca - ------ -------- I 2 D0O0E+00 I Enclosures

.00

Watesborne 3 6.600E-03 Vents

Drywell I1.00 Floor

0.03 iSdrmftent 4 0.000E+00 Floor

0.00

Waterborne 5 0.000E+00 Vents

'I.00

I.

tSedinent 6 0.OOOE+00 Floor

Condensate Drainage__

10.10

Stnxtures-Above i

0.00 lAdheres

0.00

7 0.000E+00 Structures-Above

0.90

________ _ I

Waterborne 8 4.400E-03 Vents

1.00

Recirculation Flow

1.00 -Sedirnet

Structux-Break 0.00

0.02 Adh-eres

_ 9 D .000E+00 Floor

10 0 .OOOE+00 Structures-Break ___________I ---------------------------- _ _.

0.00

Waterborne 1 I 1.320E-02 Vents

1.00

Sprays/Condensate

1.00 1S-dnt

S t ructure s-Other 00 I 00.00

0.06 1Adheres

_ I_12 0.000E+00 Floor

13 0.000E+00 Structures-Other

Structures-Break

0.25

sArge-Above

0.30

,Structures-ther

0.75

0.00

Waterborne 14 9.000E-03 Vents

.00.

Recirculation Flow

0.12 ; Sediment 15 0.000E+00 Floor

0.00

Aheres 16 6.600E-02 Structures-Break

0.88

Waterborne 17 4.500E-03 Vents

1.00

Sprays/Condensate

0.02 Sediunent I8 0.000E+00 Floor

_ 0.00

Adheres 19 2.205E-0 I Structures-Other

MSL Break

1.00

0.98

Advected to Vent 20 8.OOOE-02 Vents

| u.00 Enls s21 . __ f _ 0.000E+00 __[______ Enclosures 1.. nl... arge-HEOW e 000

0.08

DrweUl Floor

Waterborne 22 0.000E+00 Vents

1.00

10.00 ISedirnent 23 O.OOOE+00 Floor

0.00

Waterbome 24 O.OOOE+00 Vents

11.00

iSedient 25 0.Oo1E+00 Floor --------------- __

Recixculation Flow

I-------~------~

Structures-Break a

0.00-- --- ---- - s ---

0.00

26 o.oooE+00 Structures-Break

0.00

_________ -

Waterborne 27 O.oooE+00 Vents

1.00 I Sprays/Condensate I | ._______-_----4di t 1 10.0-ISediment z0.02 - ...

1Structures-Other i 0.00 O -9 0.0

0.00 'Adheres

t 28 O.OOE+00 Floor

29 O.OOOE+00 Structures-Other - -- - ---- _- _- ___- ___ 0.98

Canvassed 30 4.ODOE-01 Sturctures/Floor _ _ , _ ._ _

no Tofql I nnF.

NUREG/CR-6369 A-92
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK II

Estimate: UPPER BOUND FIBROUS INSULATION

Break: lSL BREAKl

ECCS: NOT THROTTLED

Sprays: SPRAYS OPERATED

TREE QUANTIFICATION

Debrs Cassileaion ent Encosues Foor Structures Structures Structures Transport Debris Classification Vents Enclosures Floor Above Break Other Fraction

Small Pieces 2.200E-01 O.OOOE+00 0.OOOE+00 0.000E+00 0.OOOE+00 0.OOOE+00 1.0000

Large Pieces-Above 1.350E-02 0 0.OOOE+00 0 6.600E-02 2.205E-01 0.0450

Large Pieces-Below 8.OOOE-02 I .000E+00 0;000E+00 0 0.000E+00 I .000E+00 1.0000

All Large Pieces 9.350E-02 I .000E+00 0.000E+00 0 6.600E-02 2.205E-01 0.2461

All Debris 3.135E-01 0.0E0 .O00E+00 0.000E+00 6.600E-02 2.205E-01 0.5225

All Zone-of-Influence 03135

FINAL DISTRIBUTIONS (Horizontal)

Structures Structures tructures

Debris Classification Vents Enclosures Floor Above Break Other

Small Pieces 100.00% 0.00% 0.00% 0.00% 0.00% 0

Large Pieces-Above 4.50% 0% 0.00% 0% 22.00%

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00%

All Large Pieces 24.61% 0.00% 0.00% 0% 17.37% 58.03

All Debris 52.25% 0.00% 0.00% 0.00% 11.00% 36.75

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Above Break Other

Small Pieces 70.18% N/A N/A N/A 0.00% 0.00

Large Pieces-Above 4.31% N/A N/A N/A 100.00% 100.

Large Pieces-Below 25.52% N/A N/A N/A 0.00% 0.0

All Large Pieces 29.82% N/A N/A N/A 100.00% 1

Debris Transport Fractions

1.250

1.000 -

0.750

LL 0.500

0.250

0.o00

Small Debris Large Above Large Below AJl Large Debris AJI Debris AlI Zone-ofGrabrngs Gratngs Influence

A-93 NUREG/CR-6369
Appendix A

A.4.2.2 Recirculation Line Break

This section contains upper bound estimate logic charts for Mark 11 recirculation line break scenarios.

A-95 NUREG/CR-6369
Appendix A

LOA ye eri cuifct,4Distribution After lErosion and Wasbdown Drywel]Floor Pool pahI Fraction Final Location

IBlowdown IINo.

Advected to Vents I 0.000E+00 Vents

MARK 11

UPPER BOUND

RL BREAK

ECCS THROTTLED

NO SPRAYS

FIBROUS INSULATION

Small Pieces

l0.2

00 ---. ------- _-_-_-_-_---------------I _

'Enclosures 2 0.000E+00 Enclosures I-.- ______ ______ - ______ ______ ______ ______ ______ _____

0.00

)Drywell Floor

Waterbome 3 2.200E-01 Vents 4- I

J 100

1.00 4 0.000E+00 Floor

0.00 T------------

Waterbome 5 0.000E+00 Vents

'1.00 ' I____

kSedirnent 6 0.000E+00 Floor

Condensate Drainage i

,0.10

Structures-Above i

O. o Adheres

0.00

7 0.000E+00 Stnictures-Above ___________ _ I

-------------------------------------- _

0.90

Waterbome 8 0.000E+00

1 r --

Recirculation Flow i

11.00 | ediment

StmcturesBreak | 0.00

0.00 Adheres

0.00

4 __ I9 0.OOOE+00_I Floor ___________

10 0.000E+00 Stbuctures-Break -_______ _ -

Waterborme I1 0.000E+00 Vents

1 .00

t Condensate Drainage i

io1.10 Serliment

I tructuresOther ' 0.00

0.00 1

Adheres

: 111[ 12 I 0.OOOE+00 Floor

13 0.000E+00 Structures-0ther

Structures-Break

1.00

Large-Above

0.30

I Structures-Other

0.00

Advected to Vent

0.90

Waterborne 14 3.600E-02 Vents

1.00

Recirculation Flow

0.12 Sediment 15 0.000E+00 Floor

0.00

Adheres 16 2.640E-01 Structures-Break

0.88

Waterbome 17 0.000E+00 Vents

1100

Condensate Drainage

:0.00 -Sedunent I8 0.000E+00 Floor

1 0.00

i Adheres 19 0.000E+00 Structures-Other I-...------------------------------- RL Break

1.00

1.00

20 8.0DOE-02 Vents

1.00

Enclosures -------------------- 211 0.000E+00 I Enclosures

Large-Below

0.08

0.00

Waterbome 22 0.OOOE+00 Vents

, Dywell Floor

e i.00

.1

10.00 ' Sedinment 23 0.000E+00 Floor

Watesb ne .. . 24 0.OOOE+00 Vents

:1.00

tSedimnent 25 0.OOOE+00 Floor | ________________

Recirculation Flow

a,75 -------------- ____

I StruturesBreak I

0.0 [oAdheres

0.00

26 O.OOOE+00 Structures-Break

0.00

Waterbom

_________ -

le 27 0.OOOE+00 Vents

I I1.0

Condensate Drainage 4

10.00 *Sedient

iStructures-Other | 0.00

0.00 iAdheres

t 28 0.OOOEAv00 Floor

29 0.vOOE+00 Structures-Other -- ------- _ _ __ -_ __ 1-- 

1.00

Canvassed 30 4.0OE-01 Structures/Floor _ . _ _. . __ _I

TnXl I --ow V-.l_ E -- Iv

NUREG/CR-6369 A-96
Appendix A

i

DEBRIS TRANSPORT RESULTS I

Plant Design: MARK IIE

Estimate: UPPER BOUND

Break. RL BREAK

ECCS: ECCS THROiTLED

NO SPRAYS

TREE QUANTIFICATION

Debris Classification Vents Enclosures

Small Pieces 2.200E-01 0.OOOE+00 C

Large Pieces-Above 3.600E-02 0 0

Large Pieces-Below 8.OOOE-02 0.000E+00 C

Floor Structures Structures Structures

I Above I Break I Other

Transport

Fraction

01 O.OOOE+00 I O.OOOE+00 I 0.OOOE+00 1.0000

0 2.640E-01 I 0.000E+00I 0.1200

1, I 0 0.OOE+00 O.OOOE+00 1.0000 - I 9

All Large Pieces 1.160E-01 0.OOOE+00 I 2.640E-01 0.OOOE+00 03053

0.OOOE+00 ) Al In 0.5600

FINAL DISTRIBUTIONS (Horizontal) I I' -

Debris Classification Vents Enclosures Floor Structures structures Structures

Above I Break I Other

Small Pieces 100.00% 0.00% 0.00% 0.00% 0.00% 0.00%

Large Pieces-Above 12.00% 0% 0.00% 0% 88.00% 0.00%

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00% 0.00%

All Large Pieces 30.53% 0.00% 0.00% 0% 69.47% 0.00%

All Debris 56.00% 0.00% 0.00% 0.00% 44.00% 0.00%

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Structures Structures Structures Above Break Other

Small Pieces 65.48% N/A N/A N/A 0.00% N/A

Large Pieces-Above 10.71% N/A N/A N/A 100.00% N/A

Large Pieces-Below 23.81% N/A N/A N/A 0.00% N/A

All Large Pieces 34.52% N/A N/A N/A 100.00% N/A

Debris Transport Fractions

1.250

1.000 +-

C

0

U

ILL

0.750 l- l

0.500 4-

0.250 +-

0.000

Small Debiis Large Above Large Below All Large Debris

Gratings Gratings

All Debris All Zone-ofInfluence

A-97 NUREG/CR-6369
Appendix A

.- -

LOCA Type Debris Classificado Distirlbudon After Eroon and Waahdown Drywell Floor Pool Pt Fraction Final Location

II Blowdown IINo.II

Advected to Vents I O.OOOE+00 Vents

MARKII

UPPER BOUND

RL BREAK

ECCS THRO1TLED

SPRAYS OPERATED

10.00 __0.0 +0 I --

'Encosur_ 2 0. E+00 Enclosures I- - - -- - - - -- - - -- - - - -- __ -------------- _ _ __ _ _ I

I'0R00

IDrywell Floor

Waterborne 3 2200E-01 Vents

I1.00

!>.

FIBROUS INSULATION

Small Pie(

0.22

aeAb

0.30

RL Break

1.00

eces

1.00 ISedanent

0.00

Waterborm

Condensate Drainage I

1,0.10 ISedin~t

Str es-Above oo---

0.00 mAdheres

0.90

4 0.000+00 I Floor

IC 5 0.000E+00 Vents -- ----- 6- o

t6 0.000E+00 Floor I----------

7 0.000E+00 Structures-Above ._________ F _

Waterborne 8 0.0001+00 Vents

I'1.00

Recirculation Flow I

r------____

0.00 WAdheres

0.00

t 9 0.000E+00 I Floor

10 0.000E+00 Structures-Break ,__ __ -. __ _ __ _ _

Waterbome 11 0.000E+00 Vents

i I 1.00

| Sprays.Condensate 1.

'Structures-Other ' ~0.00

0.00 Adheres

E 12 ] 0.000E+00 I Floor

13 0.000E+00 smxftmre-Other

Stricturs-Break

1.00

ove

iStractures-Other

0.00

Advected to Vent

0.00

Waterborne 14 3.600E-02 Vents

1.00

Recirculation Flow |

.12 iSediment 15 0.000E+00 Floor

0.00

Adheres 16 2.640E-01 Stnictures-Break

0.88

Waterborne 17 0.000E+00 Vents

Sprays/Condensate

-0.02 iSedimnent 18 0.0002+00 Floor

i -~0.00

tAdheres 19 0.000E+00 Structures-Other I._______________________ -________

0.98

20 8.000E-02 Vents

1.00 21 0

F----------------------------------_-____________. I T ^. ol Lage-"elow 10 .00

0.08 1

Drywell Floor

Wateborne 22 O.OOOE+00 Vents

1l.00

F:--------------__-_______ -_ - -

0.00 ISedunent 23 O.OOOE+00 Floor

0.00

Waterbome 24 0.000E+00 Vents

vSedimt 25 0.OOOE+00 Floor

Recirulation Flow

|. ----------------- 0 !d'1.00

IStirucues-Breakc "

0.__0 ___ ______ s 0.00

26 O.OOE+00 Stuces-Brak - - ---------- ______

0.00

Waterborne 27 0.000E+00 Vents

II SP'zysSCordenste I

I I' Istfucores-otther It-0 - 0.00 I Adheres I - - - - - - - - - - - - - - - - - - - - - -

_________.-28 0.0001+00 I Floor

29 O.OOOE+00 Strwtures-Other

0.98 -_ _ - - -_ - _ - - - -

Canvassed 30 4.000E-01 Structursfloor

rs an - xI . YI - 6 "'* __________ _______________

NUREG/CR-6369 A-98
Appendix A

I

DEBRIS TRANSPORT RESULTS I

Plant Design: MARK II

Estimate: UPPER BOUND

Break: RL BREAK

ECCS: ECCS THRO1TLED

Spay: PRYSOPERTD

TREE QUANTIFICATION

Debris Classification Vents Enclosure

Small Pieces 2.200E-01 0.OOOE+0C

Large Pieces-Above 3.600E-02 0

Large Pieces-Below 8.OOOE-02 0.OOOE+OC

All Large Pieces 1. 160E-01 0.000E+0C

All Debris 3.360E-01 0.000E+00

All Zone-of-Influence

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification Vents Enclosure

Srmall Pieces 100.00% 0.00%

Large Pieces-Above 12.00% 0%

Large Pieces-Below 10000 000%

All Large Pieces 30.53% 0.00%

All Debris 56.00% 0.00%

Structures Structures

Break I Other

RELATIVE CONTRIBUTIONS

Debris Classification

4 4 _. . I , I . a A I B -

Q-al PII, .311=" L i - 4 I - - -! - a * _ ; . I . } tA j A -

T r--- D;.--cAI,-. L 46 L'SI - I-" I -. u I I ;-- I a -

T rn Po~cRl--

'-4 I ' ~ '. 4-~- ~ I- 'I. - t___ All T s--- P;P.P C'. _A .. I - . I -_ L - I - . -

Debris Transport Fractions

1.250

1.000 _

£

0

ts

2

LA.

0.750 4-

0.500 t_

0.250 _--

0.000 _-

Small Debris -Large Above Large Below All Large Debris

Gratings Gratings

All Debris All Zone-ofInfluence

A-99 NUREG/CR-6369
Appendix A

LOCA Type IDebris Classificado Distribution After Erso ndWsdI DIf orPApt L Blowdow | ErosioN Washdow Drywell Floor Pol |Na od Fraction |Finl Location

Advected to Vents MARK 11 0.00 ----------------------------------------- _.OOE+OO 2 Venb

UPPER BOUND 

0.n° ---------------------------- 2 .000E+00 Enclosures

RL BREAK 

Watebone 3 2.20OOE1 Vents 'Dtyeill Floor 1.00 NOTTHROTLED 1.00 iSedirnent 4 0.000E+OO Floor

NO SPRAYS 0.00

Wateslbome FIBROUS INSULATION 5 0.0EfoVet

--- 00 - O.OOOE+OO Venb

Strictures-Above K.10 Sedinent 6 O.OOOE+OO Floor

| rl-O-O~~77--------- ---- __8 OOO+O Vn

Small Pieces- - - - 0.00 t - - 0.00 i.Adh-re5_________________ . +P 10 O0.000E+00 Structures-Above

0.2 Waebon i....OE+O Vn

0.90

Waterborne i 0.000E00 Vents

Recirculation Flow I

~a: 11.a: 0.0 sIedxnie ______ 1 9 0.OOOE+OO Floor

0.30--- 0.00-

10~ea .00 iAdheres_______________ 19 O.QOOE+OO Stoxs-nBer

* 0.00+0

1.0dvctued o n 2 .000E4Z Vents

------ - W rbm_____ 22 -- ---------- O-E+OO Venxblm-r

0:1.0

Condensate Drainage

L. -Sedi-nen 2- O.0.00E+0 Floor slOdheres ----- 0.0013 

0.00 ~ .0E+0 S tuv-te dee

Wsterbom O.OOOE+ 14 OO Vents

j ~~RecirculationFo

0.3 r Sedi0ent O.OO 18 O E+OO Floor

.Strnctures-OBrea ---- '--

1°00 1Adheres 16 .OOOEO-0 Stuctures-8reak

Wtroe20 O.OOOE+OO Venbs

Large- elow-2 

1 0.00E70

W~at --------- 22 0.000E+00 Vents

:1.00

Condensate Doainage

0_ _.0 |Sedirnent 238 O.OOOE+00 Floor

0.00

0.00terbne 24 O.OOOE+OO Vents

Canvassed----00 E

11.00?SAddvetc5ed.0to+0VFloo

1.00 0.00

0.8Waterbomne 

27 0.00+0 Vnt

C-on---sa-----ainage

i0.0ryedmeAv8 

00FloorFoo

- 0.00

Cavasd .0 0 .00-1 trcursFloor

WakiG/CRe 24 Vents

NUREG/CR-6369 A-1 00
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MARK II

Estimate: UPPER BOUND FIBROUS INSULATION

Break: RLBREAK

ECCS: NOT THROTTLE

Sprays: NO SPRAYS|

TREE QUANTIFICATION

. i _ Structures Structures Structures Transport

Debris Classification Vents Enclosures Floor Aoe Bek Ohr Fato S I I Above IOBreak Other Fract0on

Small Pieces 2.200E-01 IO.OOOE+O0 IO.OOOE3+00 O.OOOE+00 O.OOOE+00 O.OOOE+00 1.0000

Larme Pieces-Above 9.OOOE-02 0 IO.OOOE+00I 0 2.100E-01 I O.OOOE+00 0.3000

Large Pieces-Below 8.OOOE-02 O

All Large Pieces 1.700E-01 O

0 O.OOOE+00 0.OOOE+00 1.0000

2.100E-01 0.OOOE+00

m^r I. n^snA .

0.4474

All Debris 3a onrnl.A TIJU 0.6500

I n AsanA All Zone-of-Influence

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification Vents Enclosures Floor Structures Structures

Above I Break

tructures

Other

Sniall Pieces 100.00% 0.00% 0.00% 0.00% 0.00% 0.00%

Large Pieces-Above 30.00% 0% 0.00% 0% 70.00% 0.00%

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00% 0.00%

All Large Pieces 44.74% 0.00% 0.00% 0% 55.26% 0.00%

All Debris 65.00% 0.00% 0.00% 0.00% 35.00% 0.00%

RELATIVE CONTRIBUTIONS (Vertical)

Debris Classification Vents Enclosures Floor Structures Structures Structures Above Break Other

Small Pieces 56.41% N/A N/A N/A 0.00% N/A

Large Pieces-Above 23.08% N/A N/A N/A 100.00% N/A

Large Pieces-Below 20.51% N/A N/A N/A 0.00% N/A

_ 

All 

____ T -. r__,_ Pi;r... ._____ _ I A4 I. 59% I _ N/A I N/A a N/A 1vU.UU0/O IN/A

Debris Transport Fractions

orn.

1.000 1-

0

U.

0.750 +-

0.500 -

0.250

0.000

Small Debris Large Above

Gratings

Large Below All Large Debris

Gratings

All Debris All Zone-ofInfluence

A-1 01 NUREGICR-6369
Appendix A

LOCA Type Debrdbwn A | r a Drywe Floor Pool patheFraction FInal LocdIo I~brs Dtibtin lasiledo ftrIroio ad asd-No.

Atvected to Vents 0.0Q0E+00 Vents

MARK 1

UPPER BOUND

RL BREAK

NOT THROTTLED

SPRAYS OPERATED

FIBROUS INSULATION

SmaHl Pieces

10.22

10.00 -- ---- - ------------- !Enclosures 2I 0.^E+00 Enclosures I nn-- - ------. - - - - - - - - - -- - - - I__--- 

jU.LO

IDrywell Floor

Waterbonme 3 2.2u0E-41 Vents i 4 .1 ____________

11.00

,

1.00 iSedimrnnt

W--- 4 0.000E+00 Fwr ---- _____ ___ I 

0.00

Wateromrne 5 0.OOOE+00 Vents

Ip.00

__iment_6____ __. ___ 0 Floor 1Sedirnent 6 0OOO^,E+400 Floor I.__________________

Condensate Drainage

Structure-Aove

0.00 tAdheres

0.00

7 0.000E+00 Structures-Above -- ...--------------------...- ______ I 0.90

Waterborne 8 0.OOOE+00 Venft

; 1.00

Recirculation Flow i

11 t.00 ' Sedirnent

Struct Break 0.00

0.00 °Adheres

-: . 9 0.Q00E+00 Floor

10 0.000E+00 Structures-Break -- ---- -- ...nn- I----

Waterbome ii 0.000E+00 Vents

i ; 1.00

I Sprays/Condensate 1

'100 iSedinent I I1.0 I- - - -

'IStuctures-Other | 0.00

ooo -- Adheres

_________. 12. 0.000E+00 Floor

13 0.OOOE+00 Structures-Other

Structures-Break

1.00

Large-Above

0.307

i Structures-Other

0.00

Q00----------- ------- ___----- ___

Waterborne 14 9.u00E-02 Vents

Reciruation Flow -

0.30 iSedunent 15 0.000E+00 Floor

0.00

Adheres 16 2.1 00E-0 1 Structures-Break

0.70

Waterborne 1 7 0.000E+00 Venhs

Sprays/Condensate -

-002 ;Sedinent 18 0.000E+00 Floor r _ --- ...----------

Adheres 19 0.000E±00 Structures-Other L ... -.- - -------------- - - __-- UL Break

.00

0.98

Advected to Vent 20 8.OOOE-O2 Vents

|Enclosures .. 21 0.Q00E+00 j Enclosures I ___ --L Large-1low |0.00

0.08

Drywel] Floor

Waterborne 22 O.DO0E+00 Vents ---------- - -_-- - - 4 II.00

-:-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- - - -_-

10.00 *Sediment 23 O.OOOE+00 Floor

0.00

Watekborne 24 0.000E+00 Vents

I _____ 2_0 F

'Sedimnent _______. 25 O.00OOE+00 Floor

Recirculation Flow

'1.00

Structures-Break |

00 0dher

0.00

__________ t _ 

26 0.OOOE+00 . ___ . __

Structures-Break .____________________________________--

0.00

Waterborne 27 O.OOOE+00 Vents

I '1.00

Sprays/Condensate I

.0.02 - -Sedirnent

:Stnmctures-Other E ' to

0.00 iAdheres

L - 28 I 0.000E+00 Floor

29 0.OOOE+00 Structweg-Cher

0.98

_____ - _ _ _ _ I _-I _. _

Canvassed 30 4fWF0A-Ot Stuc-urcstncw L . - ; - - i - , - - - -- - i - - - , - - - , - - , 0.40 Total 1 (YYYO-.VI

NUREGICR-6369 A-1 02
Appendix A

DEBRIS TRANSPORT RESULTS I

Plant Design:

Estimate:

Break:

ECCS:

Sprays:

TREE QUANTIFIC

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

All Zone-of-Influence

FINAL DISTRIBUTI

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

RELATIVE CONT

Debris Classification

Srnall Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

_RL BREAK|

_NOT THROTTE

_SPRAYS OPERATED|

kTION

Vent Ecosues Foor Structures Structures Structures Transport Vents Enclosures Floor Above Break Other Fraction

2.200E-01 O.000E+00 O.OOOE+00 O.OOOE+00 0 O.E+00 0.000E+00 1.0000

9,000E-02 0 O.OOOE+00 0 2.100E-01 O.OOOE+00 03000

8.OOOE-02 O.OOOE+00 0.OOOE+00 0 0.OOOE+00 O.OOOE+00 1.0000

_1.700E-01 O.OOOE+00 O.OOOE+00 0 2.100E-01 0.000E+00 0.4474

_ .OE0 .000E+00 O.OOOE+00 O.OOOE+00 2.10013-01O .000E+00 0.6500

_ 03900

IOlNS (Horizontal)

Vents Enclosures Floor Structures Structures Structures l et Ecoues For Above Break Other

100.00% 0.00% 0.00% 0.00% 0.00% 0.00%

30.00% 0% 0.00% 0% 70.00% 0.00%

100.00% 0.00% 0.00% 0% 0.00% 0.00%

44.74% 0.00% 0.00% 0% 55.26%

65.00% 0.00% 0.00% 0.00% 35.00%

RIBUTIONS (Vertical)

_ . Structures Structures

Vents Enclosures Floor Abv Bra Ote _ Above Break Ote

56.41% N/A N/A N/A 0.00% N/A

23.08% N/A N/A N/A 100.00% N/A

20.51% N/A N/A N/A 0.00% N/A

43.59% N/A N/A N/A 100.00% N/A

Debris Transport Fractions

1.250 -

1.000-

0.750- .0

U.0.500

0.250

0.000

Small Debris Large Above Large Below All Large Debris All Debris Aul Zone-ofGratings Gratings Influence

A-103 A-103NUREG/CR-6369
Appendix A

A.4.3 Mark III

This section contains the upper bound estimate logic charts for the Mark IlIl design.

A.4.3.1 Main Steam Line Break

The upper bound estimate logic charts for the main steam line breaks are presented here, then the charts

for the recirculation line breaks are presented in Section A.4.3.2.

A-1 05 NUREG/CR-6369
Appendix A

LOCA Tye Debris Classificatlo Disiribtlo dAft Eroslon andWashdown DrywellFloor Pool Fraction FInal Locaion

Advected 

Blowdown to Vents

No.Ipah 

1 I.958E-01

I_ Vents_ -

MARK III

UPPER BOUND

MSL BREAK

ECCS THR(TLED

NO SPRAYS

FIBROUS INSULATION

Small Pieces

10.22

0.89

EnClosures 12- 0-)00E+00 Enclosures

0.00

Waterborne 3 0.000E+00 Vents --------- _------_ .

Dryell Floor

MOO

-___________________------------ 4 0 Sediment 4 0.000E+00 Floor

W_____.......-----

10.00 Watedime 5 0.00E+00 Venbo

,_______ ________ _ .________________ ________________________

*,Sedinwnt 6 0.000E+00 Eloor

Condensate Drainage _

.0.10

Structures-Above a

0.00 liAdheres -

1.00

7 0.OOOE+00 Structures-Above

0.90

Waterborne 8 0.OOOE+00 Vents

iO.00

Condensate Drainage I

0.10 Sedinent

Structures-Break 1.00

0.03 Adheres

__________.

:9 6.600E-04 Floor

10 5.940E-03 Structres-Break _ _ _

0.90

Waterborne 11 0.000E+00 Vents

iO.OO

Condensate Drainage i

0.10 ISediment

Struces-Other 1.00

0.08 Adheres

12 I 1.760E-03 Floor

13 1.584E-02 Stractures-Other

Structures-Break

0.25

Large-Above

0.30

Structures-Other

0.75

Advected. to Vent

0.90

Waterborne 14 0.OOOE+00 Vents

p0.00

Condensate Drainage ;

'0.00 Sediment 15 0.OOOE+00 Floor --------

1.00

Adheres 16 7.500E-02 Structres-Break

1.00

Watesbome 17 0.OOOE+00 Vents

'° .0 --------- Condensate Drainage I .___---- 4 10.00 Sedisnt 18 0.000E+00 Floor

1Adheres 2.250E-01 Structures-Other

MSL Break

1.00

1.00

20 8.O0OE402 Vents

00 _ 

Enclsure 21 0.00E+00 Encosures

Large-Below

0.08

0.00

Waterborne 22 0.OOOE+00 Vents

[Drywll Floor

i0.00

-- - - - - - - - -- - - - - - - - - 0.00 lbedunent 23 | O.OOOE+00 Floor

1.00------

WatesboMe 24 O.OOOE+40 Vents

,0.00

iSedinent 25 O.OOOE+00 Floor II_________

Condensate Drainage

10.00

Structures-Break I

0.W0 -Adheres __ _

1.00

26 O.OOOE+00 Strctsures-Break

1.00________________________ IMo .-- _ .

Watesbome 27 0.000E+00 Vents

1 '0.00

I Condensate Drainage |

II -E4 10.00 tSediment

iStructures-Other I 1.00

0.00 kAdheres

2_______Flo

___________1 28 O.OOOE+00 Floor -

29 O.OOOE+00 Structures-Other

1.00

Canvassed 30 4.000E-01 Structures/Floor t .- I I mnF-44',A I. 0.40 Total I I OOOE+OO

NUREG/CR-6369 A-106
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MIARK m

Estimate: UPPER BOUND FIBROUS INSULATION

Break: WL BREAK

ECCS:ECCSTHRO

Sprays: N SPRAYS|

TREE QUANTIFICATION

Structures Structures Structures Transport

Debris Classification Vents Enclosures Floor Abo Break Other

Snall Pieces 1.958E-01 0.000%+00 2.420E-03 0.000%+00 5.940E-03 1.5841-02 0.8900

Large Pieces-Above 0.000E+00 0 0.00%E+00 0 7.500E-02 2.250E-01 0.0000

Large Pieces-Below 8.00E-020 0.00 0.E+00 0 0.00%E+00 0.0E+00 1.0000

All Large Pieces 81.05E-02 0.00%+ 0.0E+00 0 .0E-02 2.250E-01 0.2105

All Debris 2.758E-01 % 0.00E+00 2.420%- 0 .300E+00 8.094%-02 2.4080140.4597

All Zone-of-Inlunc 0.2758

FINAL DISTRIBUEIONS (Horizontal)

Debris Classification Vents Enclosures Floor Sroue Brea Other Above Break Othe

Small Pieces 89.00% N/A 100.00% N/A 2.70% 7.20%

Large Pieces-Above 0.00% 0% 0.00% 0% 25.00% 93.42%

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00% 0.00%

All Large Pieces 21.05% 0.00% 0.00% 0% 19.74%

All Debris 45.97% 0.00% 0.40% 0.00% 13.49%

RELATIVE CONTRIBUTIONS, (Verticl

Debris ClassifiDation Vents Enclosures Floor tracturns Above Other

Small Pieces 70.99% N/A 100.00% N/A7.4

Large Pieces-Above 0.00% N/A 0.00% N/A 92.66% 9.2

LargeIPieces-Below 29.01% N/A 0.00% N/A 0.00% 0.00%/

All Large Pieces 29.01% N/A 0.00% N/A 92.66% 9.2

Debris Transport Fractions

1.250 -

1.000

0 0.750

U.0.500

0.250

0.000

Small Debris Large Above Large Below All Large Debris All Debris All Zone-ofGratngs Graflngs Influence

A-107 NUREG/CR-6369
Appendix A

LOCA Type Debris Classificato| DistributionAlter d Erosion and Wasbdown Dryweli Floor Pool I| I Fraction | Final Location

IBlowdown o -

Advected to Vents I 1.958E-01 Vents

MARK III

UPPER BOUND

MSL BREAK

NOT THROTTLED

NO SPRAYS

FiBROUS INSULATION

Srmall Pieces

10.22

0.89

Enclosures 2 I0.000E+00 Enclosures

0.00

Waterboone 3 O.000E+00 Vents ,________ ________- i 1.00

Drywell Floor _.;------------------------- - ---------

2.00 i Sedirnent

--- S ---

0.00

Waterborn

11.00

Condensate Drainage I

.I -O iSedirvent

Structures-Above i0 00

0.00 lAdheres

4 0.000E+00 Floor

ne 5 0.000E+00 Vent,

6 0.000E+00 Floor

7 0.000E+00 Structures-Above L_____________________________________

0.90

Waterborne 8 6.600E-03 Vents

1.00

Recirculation Flow

1.00 'Sedinent

Structures-Break I 0.00

0.03 eAdheres

. 9 0.000E+00 Floor

10 0.000E+00 Structures-Break

Istructures-Other

0.08

Structure-Break

0.25

Large-Above

0.30

Struchffe-dter

0.75

Advected to Vent

0.00 -------- _____

Waterborne 11 1.760E-03 Vents

1.00

Condensate Drainage

0.10 Sediment 12 0.000E+00 Floor

0.00

Adheres 13 1.584E-02 Structures-Other

0.90

Waterborne 14 9.OOOE-03 Vents

16610E02 Srctrs-ra

Recirculation Flow g I

0 - eSedimnent 15 0.000E+00 Floor

0.00

16 6.600E-02 Structures-teak

Waterborne 1 7 0.000E+00 Vents

Conderisate Drainage

10.00 1Sdnt_____ 18 0.000E+00 Floor

lAdheres 1 2.250E-01 Strucs4tuer

MSL Break

1.00

1.00

20 8.00E402 Venb

11.00

Lrge-Below ],Enclosures____________________________2_ 0.000E+00___ Enclosures

0.08

,Drywell Floor

Waterborne 22 0.000E+00 Ventb :--------____ _

i°.10

!_Sedimnt 23 0.000E+00 Floor

0.90

Waterborne 24 o.oooE+00 Vents

10.10

Tsedlirent 25 0.000E4+00 Floor

Recirculation Flow

StructureBreak I

0.00 {Adheres

0.90

26 0.000E+00 Structures-Break .1--------------------------------- -- - I 0.00

Waterbome 27 O.OOOE+00 Vents

i 1i0.10

I Condensate Drainage I

i ,0.00 jSedir.1nt

jStrctures-ther | 0.90

0.00 -Adheres

t 28 0.000E+00 Floor

29 O.OOOE+00 Structures-Other ----- ___--_____-__---_----------_- -.-

1.00

Canvassed 30 4.000E-01 Structures/Floor _ _ _

non -nh I nnn;4e

NUREG/CR-6369 A-108
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: _ ARKI

Estimate: UPPER BOUND FIBROUS INSULATION

Break MSLBREAK

ECCS: NOT THROTTLED

Sprays: NO SPRAYS

TREE QUANTIFICATION

Debris Classification Vents Enclosures Floor Arove Brea Otues Fracspon Above Break Other Fraction

Small Pieces 2.042E-01 0.000E+00 0.OOOE+00 O.OOOE+00 0.OOOE+00 1.584E-02 0.9280

Large Pieces-Above 9.OOOE-03 0 0.OOOE+00 0 6.600E-02 2.250E-01 0.0300

Large Pieces-Below 8.000E-02 0.OOOE+00 0 0.OOOE+00 I 0.OOOE+00 1.0000

All Large Pieces 8.900E-02 :60 0.OOE+00 0 6.600E-02 I 2.250E-01 0.2342

All Debris AI 0.000E+00 I 6.600E-02 I 2.408E-01 1 0.4886

All 7Ann.jf-lnfl1uPnce

FINAL DISTRIBUTIONS (Horizontal)

Debris Classification Vents Enclosures Floor Structures Itructures

I Above Break

tructures

Other

Small Pieces 92.80% 0.00% 0.00% 0.00% 0.00% 7.20%

Large Pieces-Above 3.00% 0% 0.00% 0% 22.00% 75.00%

Large Pieces-Below 100.00% 0.00% 0.00% 0% 0.00% 0.00%

All Large Pieces 23.42% 0.00% 0.00% 0% 17.37% 59.21%

All Debris 48.86% 0.00% 0.00% 0.00% 11.00% 40.14%

RELATIVE CONTRIBUTIONS (Vertical)

i EStructures Structures Structures

Debris Classificaton Vents Enclosures Floor Above Break Other

Small Pieces 69.64% N/A N/A N/A 0.00% 6.58%

T rce Pieces-Ahnve 3.07% N/A N/A N/A I 100.00% 93.42%

_ _ tw -a-- 1 _ __ 1: ._ 1 1 _ _

Large Pieces-Below 27.29% N/A N/A N/A 0.00% 0

All Large Pieces 30.36% N/A N/A N/A 100.00% 9

Debris Transport Fractions

1.250

1.000

C 0.750

0

LL. 0.500

0.250

0.000 I I I I I

Small Debris Large Above Large Below All Large Debris All Debris All Zone-ofGratings Gratings Influence

A-109 NUREG/CR-6369
Appendix A

A.4.3.2 Recirculation Line Break

This section contains the upper bound estimate logic charts for Mark III recirculation line break scenarios.

A-11 NUREG/CR-6369 1
Appendix A

LOCA Type Debris Classifcatio Dsuton After I Erosion and Wasbdown Dryweil Flo-or Pol path Fraclion | Flnal Locatlon II Blowdown II No. _______I _______

Advected to Vents I 0.000E+00 Ventb

MARK II1

UPPER BOUND

RL BREAK

0.00 --------- __ I

iEnclosures 2 0.000E+00 I Enclsures P_------_----_-__---_--__-__-----------___-__------_-_---

10.00

IDryweil Floor

Waterbome 3 2.200E-01 Ventb I f- F

11.00

ECCS THROTTLED

NO SPRAYS

FIBROUS INSULATION

Small Pieces

10.2

1.00 iSediment I---- -

0.00

Watertom

11.00

Condensate Drainage I

o.-10 ;

1

Sediment

Stnrctures-Above 0. 00 7 ----- ----

0.00 mAdheres 1.___________________________

4 0.000E+00 Floor

ne 5 0.000E+00 Vents

__________ 6 0.000E+00 Floor

7 0.000E+00 Structures-Above ___________ _-, __________________ __________________

0.90

Waterbome 8 0.000E+00 Ventb

; 1.00

* Reciuculation Flow t

1.00 I Sedirnent

IStructures-Break 0.00

,00 lAdheres to I ,....__ _ _ _ _ __ _ _ _ _ _ _

I 0.00

Waterboem

Condensate Drainage I

11°. '°Sedunent II* 00- 'StructuresOter 0.

0.00 ,Adheres

1 9 0.000E+00 ( Floor

10 0.000E+00 Structures-Break ___________

ne II 0.000E+00 Vents

12 0.000E+00 Floor

13 0.000E+00 Structures-Other

Structures-Break |

1.00

lzrge-Above

0.30 1

:Structures4)tbeT

_________________-

0.001

Advected to Vent

,.____________________________________ 0.90

Waterborne 14 3.600E-02 Vents

1.00

Recirculation Flow

0.12 Sedinent 15 0.000E+00 Floor

0.00

Adheres 16 2.640E-01 Structures-Break

0.88

Waterbome 17 0.000E+00 Ventb

11.00

Condensate Drainage 1

lo Sedinent 18 0.000E+00 Floor

rAdheres 19 0.000E+00 Structures-Other

RL Break

1.00

1.00

20 8.OOE-W02 Ventb

11.00

1L' ° nica .21 {.0.000E+.00 Enclosures

0.08e-Below r°-°

Waterbome 22 0.000E+00 Ventb

!Drvwefl Floor

- -- -- -- -- - - - - - - -

io.l0

6 .. ---- --- --- ---- --- ---- ---- ---

:0.00 !Sediment 23 | 0.0005+00 Floor

0.90

Watero__ne 24 O.OOOE+00 Vents

iSedirnent 25 O.OOE+00 Floor

Recirculation Flow

IL 1 .00

0StAtureshBreak s

0.00 'LAderes______

0.90

26 0.000E+00 Stuctures-Break

0.00

Waterborne 27 0.000E+00 Vents

0.10

Condensate Drainage I

X 10.00 -Sedirneut

SAtures-Other 0.

0.00 'Adheres

- -I _28 C0.00OE+00 I Floor

29 0.OOOE+00 Structures-Other

A______________ - _______________ 1.00

30 4.000E-01 Structures/Floor 4 + F n A T-1~t sI I A(5,A

NUREG/CR-6369 A-1 12
Appendix A

I

DEBRIS TRANSPORT RESULTS I

Plant Design:

Estimate:

Break:

ECCS:

TREE QUANTiIC

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

All Debris

All Zone-of-Influence

FINAL DISTRIBU11

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

Al Debris

_MARKII

RL BREAK

_ECCS THROTILED

AMION

Vent Ecosues Foor Structures Structures Structures Transport

V Above Break Other Fraction

2.200E-01 0.OOOE+00 0.OOOE+00 0.OOOE+00 0.OOOE+00 0.000E+00 1.0000

3.600E-02 0 0.000E+00 0 2.640E-01 0.OOOE+00 0.1200

8.OOOE-02 0.000E+00 0.OOOE+00 0 0.OOOE+00 1.0000

_1. 160E-0 1 0.000E+00 0.000E+00 0 2.640E-01 00E+0 03053

3.360E-01 0.000E+00 0.00E+00 0.000E+00 2.640E3-01 00E+0 0.5600

- 0.3360

TONS (Horizontal)

Vents Enclosures Floor Structures Structures Structures

Above Break Other

100.00% 0.00% 0.00% 0.00% 0.00%

12.00% 0% 0.00% 0% 88.00% 0.00

100.00% 0.00% 0.00% 0% 0.00% 0.00

30.53% 0.00% 0.00% 0% 69.47% 0.00

56.00% 0.00% 0.00% 0.00% 44.00% 0.00%

RIBUTIONS (Vertical)

Vetnlsue lo Structures Structures Strctre Enclosures Floor Above AVents Break Other

65.48% N/A N/A N/A 0.00% N/A

10.71% N/A N/A N/A 100.00% N/A

23.81% N/A N/A N/A 0.00% N/A

34.52% N/A N/A N/A 100.00% N/A

RELATIVE CONT

Debris Classification

Small Pieces

Large Pieces-Above

Large Pieces-Below

All Large Pieces

Debris Transport Fractions

1.250

1.000 4--

0.750

it 0.500

0.250 +-

0.000 -

Small Debiis Large Above Large Below AJI Large Debns

Grafings Grafings

All Debris All Zone-ofInfluence

A-1 13 A-113NUREG/CR-6369
Appendix A

LOCA Type Dbris aiao Distribution After Erosion and Wasbdown Drywell Floor Pool Path Fraction Final Location

Type DbriswCawnifIaI BIdNo.I

Advected to Vents I I 0.000E+00 Vents

MARK 111

UPPER BOUND

RL BREAK

NOT THROTILED

NO SPRAYS

FIBROUS INSULATION

Small Pieces

10.22

.0.0 loWoo ------- -c-------osures I 2-[------------ II

,Enclosuzes ------------- ---------- 2 0.000E+00 Enclosures

IDiywel Floor

Wateromne 3 2.200E-01 Vents . . I.

I1.00

!^ 1.00 1iSSedirnent 4 0.000E+00 Floor

0.00

WateIbome 5 0.000E+00 Vent

fSedimernt 6 0.000E+00 Floor I---------------_

Condensate Drainage-_

I0.10

Structea-Above i

0.00 Anheres

0.00

_________, 7 0.000E+00 Structures-Above

0.90 __________.

Watetbome 8 0.000E+00 Vents

1 1.00

Recirculation Flow I ------------- 'Sedimnst 11.00 ---- --

St2nhtsr reak --- o 0.00 r -- -r 0.00 IAdheres

0.00

- 9 0.000E+00 Floor

10 0.000E+00 Structures-Break -________.

Waterbomre 11 0.OOE+00 Vents

; l .00

II Condensate Drainage i

'0 O10 iSedinent I. I -

StructuresOther 1 0.00

n n--Adheres

________. 12 {_0.000E+00 Floor

13 0.000E+00 Structures-Other

Stnxwres-Break

1.00

Large-Above

0.30

iStructures-Other

0.00

0.90

Waterborne 14 9.000E-02 Vents

1.00

Recirculation Flow

0.30 Sediment 15 0.000E+00 Floor

0.00

Adheres 16 2.100E-01 Structures-Break

0.70

Waterbomne 17 0.000E+00 Vents

1t.00

Condensate Drainage i

l0.00 ;Sedument 18 0.000E+00 Floor

0.00

TAdheres 19 0.000E+00 Structures-Other

R.L Break

1.00

1.00

Advected 20 8.00uE-02 Vents to Vent

|1.00 . . 21.. 0.000E+00 I Enclosures

= ie-Below i0.00

0.08

lDrywell Floor

Waterbome 22 0.000E+00 Vents - - -Ii0.10

.__________________________,,

10.oo *Sediment 23 0.000E+00 Floor

0.90

Waterbome 24 0.000E+00 Vents

10.10 ----------

LSediment 25 0.OOOE+00 Floor

Recirculation Flow

Src ures-Break__

0.00 lAdheres

0.90

26 0.OOOE+00 Structues-Break

Canvassed

0.00

Waterbome 27 0.000E+00 Vents

i '0.10

i Condessate Drainage I

i0.50 -o Sediment

IStructures-Other |0 g - 0 -- r-____ ___---_ _ 0.00 L.Adheres-- - - - - - - - - -

I.2_________

28 A.OOOE+00 Floor -__________.

29 0.000E+00 Structurs-Other

1.00 .- ________ l

30 4.000E-0l Strures/Floor 4- 4.

Awn Tar-.. II l)F+O W.q _. __I 6 w

NUREG/CR-6369 A-114
Appendix A

DEBRIS TRANSPORT RESULTS

Plant Design: MIARK m

Estimate: UPE BON FIRU INSLAIO

Break. RL BREAK

ECCS: NOT THROTTLED

Sprays: NO SPRAYS

TE QUAN11CICATION

DebisClasiictio Vnts Enloure Foo Structures Structures Structures Transport

Above Break Other Fraction

Smnal Pieces 2.200E-01 O.OOOE+00 O.OOOE+00 O.OOuE+00 O.OOOE3+00 O.OOOE+00 1.0000

Large Pieces-Above 9.OOOE-02 0 0.000E+u 0 2.100E-01 0.OOOE+00 03000

Large Pieces-Below 8.OOOE-02 O.OOOE+00 0.0OE+00 0 O.OOOE+00 0.OOOE+00 1.0000

.- - -. - -. _ . ^A I - A - I , AA n Afu, fA ,,afAr n An nn AA-VA

1 .700E-u0 U.uVWtA- u L.Iv~Ur~l I .UUvz-UU V.," I

3.900E-01 0.6500

fl 1J-ee 0.3900

FINAL DISTRIBUTIONS (Horizontal) . .

Debris Classification Vents Enclosures Floor Structures IStructures Structures

I Above Break Other

Small Pieces 100.00% 0.00% 0.00% 0.00% 0.00% 0.00%

Large Pieces-Above 30.00% 0% 0.00% 0% 70.00% 0.00%

Large Pieces-Below lw.00% 0.0u% 0.00% 0% 0.00% 0.00%

All Large Pieces 44.74% 0.00% 0.00% 0% 55.26% 0.00%

All Debris 65.0% I 0.00% 0.00% 0.00% 35.00% 0.00%

RELATIVE CONTRIBUTIONS (Vertica)

Debris Classification Vents Enclosures Floor Above Break Other

Small Pieces 56.41% N/A N/A N/A 0.00% N/A

Large Pieces-Above 23.08% N/A N/A N/A 100.00% N/A

Large Pieces-Below 20.51% N/A N/A N/A 0.00% N/A

All Large Pieces 43.59% N/A N/A N/A 100.00% N/A

Debris Transport Fractions

1.250

1.000 fC0

W

'U.

0.750 -4--

0.500 _-

0.250

O.OO

| I - I N|

Small Debris Large Above Large Below All Large Debris

Gratings Gratings

All Debris All Zone-ofInfluence

A-1 15 ANUREG/CR-6369
NRC FORM 335 U.S. NUCLEAR REGULATORY COMMISSION 1. REPORT NUMBER

(2-89) (Assigned by NRC, Add Vol., Supp., Rev.,

NRCM 1102, BIBLIOGRAPHIC DATA SHEET and Addendum Numbers, if any.)

3201, 3202 BBIGAHCDT HE

(See instructions on the reverse) NUREG/CR-6369, Vol. 1

2. TITLE AND SUBTITLE SEA 97-3105-A: 14

Drywell Debris Transport Study 3. DATE REPORT PUBLISHED

MONTH YEAR

September _ q _q

4. FIN OR GRANT NUMBER

W6325

5. AUTHOR(S) 6. TYPE OF REPORT

D.V. Rao, C. Shaffer, E. Haskin Final

7. PERIOD COVERED (Inclusive Dates)

8. PERFORMING ORGANIZATION - NAME AND ADDRESS (If NRC, provide Division, Office or Region, U.S. Nuclear Regulatory Commission, and mailing address; if contractor,

provide name and mailing address.)

Science and Engineering Associates, Inc.

6100 Uptown Blvd. NE

Albuquerque, NM 87110

9. SPONSORING ORGANIZATION - NAME AND ADDRESS (If NRC, type "Same as above; if contractor, provide NRC Division, Office or Region, U.S. Nuclear Regulatory Commission,

and mailing address.)

Division of Engineering Technology

Officeof Nuclear Regulatory Research

U.S. Nuclear Regulatory Commission

Washington, DC 20555-0001

10. SUPPLEMENTARY NOTES

M. Marshall. NRC Project Manaqer

11. ABSTRACT (200 words or less)

This report describes results of the drywell debris transport study. The objective of the study is to develop a methodology for

estimating fraction of LOCA generated fibrous insulation debris that would be t ransported from the location of their generation

in the drywell to the suppression pool. The study decomposed the problem into several components that were amenable to

resolution by the knowledge base that can be developed from separate effects ex periments, analytical modeling and

engineering calculations. Experiments and analytical studies were undertaken t o compile the necessary knowledge base on

debris transport during blowdown, washdown of debris by ECCS water flow and debris sedimentation on the drywell floor.

Logic charts were used to link both experimental and analytical results. The r esults of the study were used to delineate plant

features and transport phenomena that dominate debris transport in the BWR dryw ell. A separate logic chart was developed

for each postulated accident scenario and generic plant type analyzed. The log ic charts can be modified to take into account

effects of the plant specific features. The overall method is comprehensible t o engineers who are not experts in the subject of

debris transport. Also, it is sufficiently flexible that new evidence and assu mptions, related to debris size and distribution, can

be easily accommodated.

12. KEY WORDS/DESC RI PTORS (List words or phrases that will assist researchers in locating the report.) 13. AVAILABILITY STATEMENT

BWR Suction Strainers unlimited

Drywell Debris Transport 14. SECURITY CLASSIFICATION

Transport Experiment (This Page)

Computational Fluid Dynamics unclassified

Transport Fractions (This Report)

unclassified

15. NUMBER OF PAGES

16. PRICE

NRC FORM 335 (2-89)
Federal Recycling Program
ISBN 0-16-050193-8

9 78 1 111 50193 9 780160 501937 -- -
UNITED STATES

NUCLEAR REGULATORY COMMISSION

WASHINGTON, DC 20555-0001

SPECIAL STANDARD MAIL

POSTAGE AND FEES PAID

USNRC

PERMIT NO. G-67

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PENALTY FOR PRIVATE USE, $300