NUREG/IA-0203

M International 

* Agreement Report 

Assessment of RELAP5/MOD3.2.2y 

Against Flooding Database in 

Horizontal-to-Inclined Pipes 

Prepared by 

H.T. Kim, H.C. No 

Korea Advanced Institute of Science and Technology 

373-1, Gusung-Dong, Yusung-Ku, Taejon 305-701 Korea 

S.J. Ha, N.S. Ahn 

Korea Electric Power Research Institute 

103-16 Munji-Dong, Yusung-Ku, Taejon 305-380 Korea 

Y.S. Bang 

Korea Institute of Nuclear Safety 

PO Box 114, Yuseong-Gu, Taejon 305-600 Korea 

Office of Nuclear Regulatory Research 

U.S. Nuclear Regulatory Commission 

Washington, DC 20555-0001 

July 2001 

Prepared as part of 

The Agreement on Research Participation and Technical Exchange 

under the International Code Application and Maintenance Program (CAMP) 

Published by 

U.S. Nuclear Regulatory Commission
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NUREG/IA-0203

International 

Agreement Report 

Assessment of RELAP5/MOD3.2.2y 

Against Flooding Database in 

Horizontal-to-Inclined Pipes 

Prepared by 

H.T. Kim, H.C. No 

Korea Advanced Institute of Science and Technology 

373-1, Gusung-Dong, Yusung-Ku, Taejon 305-701 Korea 

S.J. Ha, N.S. Ahn 

Korea Electric Power Research Institute 

103-16 Munji-Dong, Yusung-Ku, Taejon 305-380 Korea 

Y.S. Bang 

Korea Institute of Nuclear Safety 

PO Box 114, Yuseong-Gu, Taejon 305-600 Korea 

Office of Nuclear Regulatory Research 

U.S. Nuclear Regulatory Commission 

Washington, DC 20555-0001 

July 2001 

Prepared as part of 

The Agreement on Research Participation and Technical Exchange 

under the International Code Application and Maintenance Program (CAMP) 

Published by 

U.S. Nuclear Regulatory Commission
Assessment of RELAP5/MOD3.2.2y Against 

Flooding Database in Horizontal-to-Inclined Pipes 

ABSTRACT 

A total of 356 experimental data for the onset of flooding are compiled for the data bank and used 

for the assessment of RELAP5/MOD3.2.2y predictions of Counter-Current Flow Limitation (CCFL) in 

horizontal-to-inclined pipes simulating a PWR hot leg. 

RELAP5 calculations show that higher gas flow rates are required to initiate the flooding compared 

with the experimental data if the L/D is as low as that of the hot legs of typical PWRs. 

Based on the present data bank, the new CCFL correlation is derived, which shows the L/D effect. 

The present correlation agrees well with the database within the prediction error, 8.7% and it is 

implemented into the RELAP5 and validated against the data bank. 

The predictions of the flooding limit by the modified version lie well on the applied CCFL curve 

even ifithe predictions by standard RELAP5 are lower than the present CCFL curve. 

Key Words: RELAP5/MOD3.2, CCFL, Flooding Database

111
ABSTRACT 

CONTENTS 

LIST OF TABLES 

LIST OF FIGURES 

SUMMARY 

NOMENCLATURES 

1. Introduction---

2. The Flooding Database ...................... 

2.1. Length-to-Diameter Ratio (L/D) Effect on CCFL .......... 

2.2. Inclination Angle (0) of Elbow Effect on CCFL ........... 

2.3. Development of Empirical Flooding Correlation .......

4 

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

3. RELAP5 Model .............................................. 11 

3.1. Code Description ............ .................................... 11 

3.2. RELAP5 Nodalization ........... ................................. 11 

3.3. Simulation Procedure .......... .................................. 12 

4. Code Calculations of the Database ....... ........................... 15 

4.1. Length-to-Diameter Ratio (L/D) Effect on RELAP5 Predictions ..... ............ 15 

4.2. Inclination Angle (0) of Elbow Effect on RELAP5 Predictions ................. 16 

5. Application of Empirical Flooding Correlation to RELAP5 ........... 17 

5.1. Modification of RELAP5/MOD3.2.2y ........ .......................... 17

v

CONTENTS

iii

v 

Vi 

vii 

viii 

ix
5.2. Comparison of Code Calculation Results by Standard and Modified Versions ...... .20 

6. Conclusions ......... ........................................ 22 

References ......................................... 23 

Appendix A. Sample Input Deck for CCFL Test 

Appendix B. Modification Parts in the RELAP5 Subroutines 

Appendix C. Flooding Dat~abase

vi
LIST OF TABLES 

Table 1 Experimental Flooding Data for CCFL in Horizontal-to-Inclined Pipes ........... 4 

Table 2 Input Requirement for CCFL Data Card ....... ....................... 17 

LIST OF FIGURES 

Fig. 1 General Configuration of the CCFL Test ...... ....................... 3 

Fig. 2 Experimental Flooding Points from the Present Database .................... 5 

Fig. 3 Effect of Horizontal Pipe Length-to-Diameter Ratio on CCFL ................. 6 

Fig. 4 Effect of Inclination Angle of Elbow on CCFL ....... .................... 7 

Fig. 5 Comparison between the Present Database and Empirical Correlation ............ 9 

Fig. 6 Comparison between the Present Empirical Correlation and NO and Choi's Data . - 10 

Fig. 7 RELAP5 Nodalization of CCFL Test in a Horizontal-to-Inclined Pipe ........ 13 

Fig. 8 Variation of Gas and Liquid Flow Rates at the Onset of CCFL ........... 14 

Fig. 9 Comparison of RELAP5 with Experimental Results with Various L/Ds .......... 15 

Fig. 10 Effect of Inclination Angle on RELAP5 Calculations ...... ................ 16 

Fig. 11 Flow Chart of the Subroutine CCFL ........ ......................... 18 

Fig. 12 Flow Chart of the Modified Subroutine RPIPE ...... ................... 19 

Fig. 13 Comparison of Experimental Data with Small L/D With Predictions by Standard & 

M odified RELAP5 . . . . . . . . . . . . . . . . . . .. . . . . . . .. .... . 21 

Fig. 14 Comparison of Experimental Data with Large L/D With Predictions by Standard & 

Modified RELAP5 -.. ......... ................................. 21

vii
SUMMARY 

A total of 356 experimental data for the onset of flooding are compiled for the data bank and used 

for the assessment of RELAPS!MOD3.2.2y predictions of Counter-Current Flow Limitation (CCFL) in 

horizontal-to-inclined pipes simulating a PWR hot leg. 

The predictions of the flooding gas velocity in the database are known to be largely dependent on 

the horizontal pipe length-to-diameter ratio (L/D). RELAP5 calculations are compared with the 

experimental data where L/D lis varied within the range of database. 

RELAP5 calculations show that the RELAP5 predicts the flooding points qualitatively well but 

higher gas flow rate is required to initiate the flooding compared with the experimental data if the L/D 

is as low as that of the hot legs of typical PWRs. 

Based on the present data bank, the new CCFL correlation is derived, which shows the L/D effect. 

The present correlation agrees; well with the database within the prediction error, 8.7%. The result of 

empirical correlation based on the present data bank is as follows: 

-*05 0 

-+ 0.614 ;O = 0.635 - 0.00254 

Standard RELAP5 code is modified to apply the present empirical CCFL curve to the horizontal 

volumes. The predictions of the flooding limit by the modified version lie well on the applied CCFL 

curve even if the predictions by standard RELAP5 are lower than the present CCFL curve.

VIII
NOMENCLATURES 

L Length of horizontal part of test section (m) 

D Diameter of test section (in) 

I Length of inclined part of test section (m) 

m Slope at Wallis type flooding correlation 

c Intercept at Wallis type flooding correlation 

g Gravitational acceleration (m/sec 2

) 

La Laplace capillary constant 

w Defined in Eq. (3) 

Jk Superficial velocity for k phase (m/sec) 

A, Dimensionless superficial velocity for k phase 

Greek 

0 Inclination angle of test section (o) 

p Density (m3

/kg) 

a Surface tension (N/m) 

P3 A number from 0 to 1 in Eq. (3) 

Subscript 

f For liquid phase 

g For gas phase

ix
1. Introduction

Counter-Current Flow Limitation (CCFL) of steam and water can be observed in the hot leg during 

emergency core cooling following a Loss-of Coolant Accident (LOCA). When saturated water 

condensed in the Steam Generator (SG) tubes drains back down into the reactor vessel via the hot leg 

(reflux condensation cooling mode), the possibility that steam previously boiled off in the core could 

partly or totally inhibit the water back down flow is one of the important concerns regarding the safety 

analysis of the Pressurized Water Reactor (PWR). 

A general CCFL model (Riemke, 1991) was implemented in RELAP5/MOD3 that allows the user 

to select the Wallis form, the Kutateladze form, or a form in between the Wallis and Kutateladze 

forms: 

H n+m H• c, (1) 

where subscript f is for liquid phase, subscript g is for gas phase, m is a slope and c is a gas 

intercept and the dimensionless fluxes have the form: 

F 71/2 

H, J, 8, k=f,g (2) 

where jk is the superficial velocity for each phase, g is a gravitational acceleration and w is given 

by the expression: 

w = D'-"La", (3) 

where D is a junction hydraulic diameter and L is the Laplace capillary constant given by:

I
La (4 La g(Pf U Pg) ]12(4) 

where cy is the surface tension. In Eq. (3), P3 can be a number from 0 to 1. For 13=0, the Wallis form 

of the CCFL equation is obtained, and for 13=1, the Kutateladze form of CCFL equation is obtained. 

For 0<13<1, a combination of the Wallis and Kutateladze form is obtained. The RELAP5 input is made 

general so that the user can input CCFL correlations for the particular geometry of interest in the 

volumes with the inclination anigle over than 45'. 

use the CCFL curve given by user also in the horizontal volum es, N O and Heo (2000) extended 

the CCFL model of RELAP5 for the vertical volumes (>45') to the horizontal volumes and enabled 

the user to input the information of length-to-diameter ratio (L/D) into the gas intercept, c in Eq. (1). 

However, if the flooding limit by the interfacial and the wall drags are higher than that by the flooding 

curve, NO's model cannot be applied to the simulation of CCFL in the horizontal volumes. In the 

present study the interfacial and the wall drags are reduced when flooding occurs at lower gas velocity 

than predicted by the CCFL curve in standard RELAP5. 

Through a literature survey as shown in Table 1, a data bank is constructed: 356 data in terms of 

dimensionless Wallis-type gas velocities and liquid velocities identified with the geometrical 

conditions such as horizontal pipe diameter (D), length (L) and the inclination angle (0) of the bend. 

Figure 1 shows the general configuration of the CCFL test facility. 

RELAP5 nodalization is developed for the simulation of the experiments in the database. To 

simulate the experimental results, the geometries of the horizontal-to-inclined pipes in the RELAP5 

model are maintained the same as those of the experimental conditions. The parametric effects on 

flooding are investigated by comparing RELAP5 results with the experimental data selected from the 

data bank covering a wide range of the parameters.

2
Air

Fig. 1. General Configuration of the CCFL Test

3
2. The Flooding Database

From the literature survey a considerable amount of flooding data has been collected together to 

form a data bank containing 3515 flooding points. Most of data points are the measurements of the 

onset of flooding limits in air-water counter-current flows in horizontal tubes connected at the water 

inlet to the elbows with the inclination angles from 35' to 90'. Table 1 summarizes the sources of 

flooding data and gives details of tube geometries and the inclination angles of bends. Figure 2 

presents the flooding data points in graphical form and the dimensionless gas and liquid velocities are 

the dimensionless superficial velocities from the Wallis form of CCFL equation. 

Table 1. Experimental Flooding Data for CCFL in Horizontal-to-Inclined Pipes

Ref.

Ohnuki (1986) 

Wan (1986) 

Siddiqui (1986) 

Kawaji (1991) 

UPFT(1993) 

MHYRESA (1995) 

Wongwises (1996) 

Kang (1999)

Tube diameter 

range (m) 

0.026, 0.076 

0.051 

0.038 - 0.047 

0.051 

0.75 

0.351 

0.064 

0.04, 0.08

Tube length 

range (m) 

0.01 -. 0.4 

2.958 

1.82- 2.36 

2.54 

7.086 

2.645 

0.557 - 1.408 

0.7- 3.388

Inclination angle 

of riser (0) 

400' 450 

900 

900 

900 

500 

500 

500- 900 

35'

In the experiments by Kawaji (1991), Wongwises (1996), and Kang (KAIST, 1999), the flooding 

curve is divided into three regions due to a change in the flooding mechanism. In these cases the 

flooding data points are confined to the first region (Wongwises, 1996), where the air flow rate that

4

Number of 

data points 

146 

18 

32 

7 

7 

9 

104 

33
creates the onset of flooding decreases, while the water flow rate increases. Therefore, all the flooding 

data points obtained are close to the widely accepted Wallis correlation.

0.9 

0.8 

0.7 

0.6 

0" 0.5 

0.4 

0.3 

0.2 

0.1

0.0 0.2 0.4 

- *0.5 

if

0.6 0.8

Fig. 2. Experimental Flooding Points from the Present Database 

The experiments on flooding in horizontal-to-inclined pipes were conducted over different 

conditions, such as tube diameter (D), length (L), inclination of the elbow (0), radius of curvature of 

the elbow, and inlet or exit geometry of tube. Ohnuki (1986), Siddiqui (1986), Wongwises, and Kang 

found that flooding limit in a horizontal-to-inclined pipe is strongly dependent on the length-to

diameter ratio (L/D) within the range of experimental tests. The effects of other parameters are not 

clear and inappropriate for RELAP5 code modelling except the parameter, 0. 

Therefore, 2 parametric effects, L/D and 0 on flooding limits are investigated in this study. And the 

effects of geometric parameters on CCFL are used to correlate all the data in Table I by the linear 

relationship expressed in Wallis-type correlation.

5

I 

5... . 

: *** ** *. 

I 

.. .. 

* *4*.. * 

* * * . .. * *cJ,. * * 

:p 

.. .*

I I I

I I
2.1. Length-to-Diameter R:tio (L/D) Effect on CCFL 

Ohnuki, Siddiqui, Wongwises, and Kang performed experiments in which the length of the 

horizontal pipe was varied. According to their results a longer horizontal length causes the water level 

to be higher in the vicinity of the bend due to an increase in frictions at the wall and interface and 

slows down the water flow. This, in turn, induces a higher gas velocity and hence an earlier formation 

of unstable wave growth at the hydraulic jump. 

The CCFL data obtained from the data bank with 4 different L/Ds are shown in Fig. 3. These 4 data 

sets are selected such that they represent various ranges of L/D from the different sources of 

experiments available. Since a larger L/D corresponds to a longer horizontal pipe length for a given 

pipe diameter, the lower L/D, the higher the flooding curve in Fig. 3.

0

0.7 

0.6 

0.5 

0.4

0.3 

0.2 

0.1 

-0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 

if *0.5

0.8

Fig. 3. Effect of Horizontal Pipe Length-to-Diameter Ratio on CCFL

6

0

L/D 

0 3.0 (Ohnuki) 

"- . 22 (Wongwises) 

..... A 49.8 (Kawaji) 

... 58 (Wan) 

0 

-... A. 0 

"". "-. . 

-.. 

o

I I I I . I . I . .1 Ii f . J .

•.•
2.2. Inclination Angle (0) of Elbow Effect on CCFL 

The variation of the inclination angle (0) of elbow in the present data bank ranges from 35' to 900. 

To compare the flooding points for different inclination angle of elbow, 3 data sets from Wongwises 

(LID = 22) and I data set from Kang (L/D = 25) are selected and plotted in Fig. 4. The flooding points 

with different 0 show the similar results indicating that the 0 effect on them is not so clear as in the 

case of the L/D effect on CCFL.

0.00 0.05 0.10 0.15 

if*0.5

0.20 0.25 0.30

Fig. 4. Effect of Inclination Angle of Elbow on CCFL

7

0.58 

0.56 

0.54 

0.52 

6 % 0.50 

0.48 

0.46 

0.44 

0.42

* I * I I * I 

0 350 (Kang) 

01 500 (Wongwises) 

0 .750 

V 90 

0 t o 

92....A

0."-

I . I I * I - | I

I I 1 I l 1 . . . . . . .

I
2.3. Development of Empirical Flooding Correlation

Most of the existing data or CCFL are empirically correlated by the form of the Wallis correlation 

as. 

• *0 5 -*0.5 

jg + m Jf = c. (5) 

Knowing that the deviation of the data points in Fig. 2 is mainly due to the L/D effect, the best 

fitting correlation is developed for the prediction of flooding points. The regression of the existing data 

points is conducted to find the constant, m, and the gas intercept, c. The following empirical 

correlation based on the present data bank is derived: 

-)O +0.6141;o= 0.635-0.00254 ( . (6) 

The L/D effect on CCFL is also considered in Ohnuki's correlation and Kang's correlation as 

follows: 

j + 0.75 J0 in[( L )(j]j 6+ 0.88, for Ohnuki's correlation (7) 

Jg + 0.397 j, = 0.603 - 0.00234 , for Kang's correlation (8) 

where I is the length of the riser (inclined section). 

The predictions of the empirical correlations are compared with the experimental flooding data 

bank. Comparison of the present correlation with the database is displayed graphically in Fig. 5 and 

the percentage error is defined as: 

r0)5 -*0 5

8
where n = total number of flooding data points -*0.5 

J = predicted flooding gas dimensionless superficial velocity 

Jý, -*0 5 e experimental flooding gas dimensionless superficial velocity

The present empirical correlation agrees well with the database within the prediction error, 8.7%. 

Ohnuki's correlation predicts Ohnuki's data within 9.4% and Kang's correlation predicts Kang's data 

within 2.9%. However, the Ohnuki's correlation and the Kang's correlation have the prediction errors, 

12.2% and 10.7% for the all database, respectively. 

Total error (8.7 %) 

0.8 0 Ohunki (15.7 %) 0 

r- Wan (5.9 %) 

z Siddiqui (5.7 %) o Zo o 0 

Kawaji (2.1 %) 

> UPTF (2.2%O/) 

-N 0.6 MRYRESA 1 (0.7 %) 

"x Wongwises (2.3 %) 0 oo 

E Kang(7.6%) /60 C 

? 0.4 0 c 

0o 0.2~~ 0 0000

0.2 0.4 0.6 * *0.5 ig from correlation

Fig. 5. Comparison between the Present Database and Empirical Correlation

9
NO and Choi (1995) developed a flooding correlation from their experimental studies of flooding 

in nearly horizontal pipes. It is interesting that NO and Choi's flooding data are well predicted by the 

present empirical correlation as shown in Fig. 6.

0.6 

0.5 

0.4

0.3 

0.2 

0.1 

0.0

0.0 0.2 0.4 0.6 0.8 1.0 

S*0.5 

Jf

Fig. 6. Comparison between the Present Empirical Correlation and NO and Choi's Data

10

"Choi's correlation "x,•j °1/2 1 /2 

X, jg +0 .64jf =0.58 

"00 3 

10 

00 

Present: correlation o C) -.. ~ 

J•+0.6)1 4jr "0.56 0• 

0 NO and Choi's data 

(D--0.07m, L-2.]6m)

m
3. RELAP5 Model 

3.1. Code Description 

The assessment calculation for sample problems and CCFL experiments in the database are done 

using RELAP5/MOD3.2.2y computer code fixed for crossflow junction subscripts. Subscript errors 

were discovered by Won-Jai Lee (KAERI) in the vexplt subroutine for the crossflow junctions. These 

errors are known to affect the crossflow wall friction. Therefore, in a problem like CCFL, which has a 

cell with a crossflow junction, the patched code should be used. The correction in the vexplt 

subroutine was to change the kf and If subscripts on rhof and rhog to k and I, respectively. The code is 

patched on SUNW SPARCstation 20 system operating under Solaris 2.6. The computer is a 32-bit 

workstaion with 128MB of RAM memory and 167 MHz of clock speed. 

In this study assessment of version 3.2.2 Gamma for CCFL in the horizontal-to-inclined pipes is 

done and the standard version is improved, as is the standard practice for developmental versions of 

RELAP5. 

3.2. RELAP5 Nodalization 

RELAP5 nodalization is developed for the simulation of the experimental results as shown in Fig. 

7. The RELAP5 nodalization used in the present calculation is fixed to the same type as the CCFL test 

facility at KAIST (Kang's experiment). 

Water is injected into the test section (Pipe-100) from the right plenum (Branch-340) and air from 

the left plenum (Pipe-230). Flow boundary conditions of water and air are modelled as time dependent 

junctions, TDV-315 and TDV-215, respectively. Water is drained into the left plenum (Pipe-230) and 

the time dependent junction, TDJ-250, controls the water inventory in the left plenum such that the

II
water flow rate to water outlet (TDV-260) is equal to one from the test section. Air flows out to the 

right plenum and flows up into the upper plenum (Pipe-350). And then air is vented to the time 

dependent volume, TDV-360, that is modelled as a pressure boundary. 

The test section is modelled as a pipe component divided into horizontal volumes and inclined 

volumes. Flow area and the horizontal volume length of the test section are determined by D and L 

from the database. The inclination angle (0) of the elbow is applied to the inclined volumes. 

3.3. Simulation Procedure 

The RELAP5 calculations folow the experimental procedures of allowing the liquid flow to settle 

down into a steady state before increasing the gas injection rate. Water flow is ramped up from zero to 

a given flow rate corresponding to the dimensionless superficial liquid velocity of the simulated 

database. While the water flow is maintained constant, the air flow is increased slowly until the onset 

of flooding is observed. 

The onset of horizontal flooding is brought out, in RELAP5, by the rapid and very large increase of 

interface friction, which happens as the flow regime changes from stratified to slug flow. And the 

transition from stratified to slug flow induces the oscillatory behavior of void fraction, mass flow rate, 

pressure. Figure 8 shows the behavior of mass flow rates of liquid and gas during the simulation of the 

onset of CCFL. 

At the moment the liquid flow rate in the horizontal test section has limitation and shows the 

fluctuation, the flooding gas flow rate is roughly determined. And after some trial and error 

calculations for the fixed water and air flow rates, we can obtain more correct flooding points.

12
P: Pipe 

B Branch 

J Single Junction 

TDJ : Time-dependent Junction 

TDV: Time-dependent Volume

Fig. 7. RELAP5 Nodalization of CCFL Test in a Horizontal-to-Inclined Pipe

13

TDJ 250
0.016 

0.40 

0.014 04 

0.012 ,." 035 Onset of CCFL 

0.010 0.30 

0.008 S0.008 0.25 

0.006 0.20 :2 

0.004 

015 

0.002 

0.10 

0 .0 0 0 " .5 0. 

, ' '-" i , i i i0.05 

0 50 100 150 200 250 300 350 400 450 

Time (sec) 

Fig. 8. Variation of Gas and Liquid Flow Rates at the Onset of CCFL

14
4. Code Calculations of the Database 

4.1. Length-to-Diameter Ratio (LID) Effect on RELAP5 Predictions 

The experimental results with different L/Ds are simulated by RELAP5. For each dimensionless 

liquid superficial velocity from experimental data the critical gas superficial velocity is obtained by 

RELAP5. The range of L/D is from 3.0 to 58.0 as shown in Fig. 9. The relationship between L/Ds and 

critical gas flow rates required to initiate CCFL is also confirmed in RELAP5 calculations. Comparing 

the RELAP5 results with experimental data, we can see that RELAP5 predicts the flooding points 

closely but higher gas flow rates than those from real data where L/D is as low as that of the hot legs 

of typical PWRs. 

0.7 0 

A O 

0.6 

G 0 037.3D 

0 0 31 

. 

Z' 13 

(}22 

0.3- 38 

S42 

" 49.8 

0.2 0 58 

I * I * I I * I * I 

0.2 0.3 0.4 0.5 0.6 0.7 

j'0 (Experiment) 

Fig. 9. Comparison of RELAP5 with Experimental Results with Various L/Ds

15
4.2. Inclination Angle (0,) of Elbow Effect on RELAP5 Predictions 

RELAP5 calculations are compared with the flooding data points for different inclination angles. 

To avoid the L/D effects on CCFL, the experimental results with the same L/D (=25) are simulated by 

RELAP5. The calculation restults and experimental data are plotted in Fig. 10. The percentage error 

between RELAP5 results and data points is within 2%. In RELAP5 calculations the flooding points 

are always the same for the di.ferent inclination angles, because the CCFL in the inclined region is 

less restrictive than that in the horizontal region. 

-- f '-I I I 

0.58 L/D=25 

0.56 0.56 -Experiment 

35 -900 

0.54 RELAP5 

"35 

0.50 0 

o. I.. 

0.48 

0.46 " 

0.44 0 

01 

0.42 * I I I I 1 I 

0.0C 0.05 0.10 0.15 0.20 0.25 0.30 

. *0.5 

Jf 

Fig. 10. effect of Inclination Angle on RELAP5 Calculations

16
5. Application of Empirical Flooding Correlation to RELAP5

5.1. Modification ofRELAP5/MOD3.2.2y 

The original CCFL model in the standard version is used only for the volume cell whose 

inclination angle is higher than 45 degree (vertical volume). However, the restriction of the inclination 

angle on the application of CCFL model is removed. The flow chart of the CCFL subroutine in the 

standard version is shown in Fig. 11. In the CCFL subroutine of the modified version we comment on 

the if statement that checks if the volume is vertically oriented (see Appendix B). 

The R-level input processing subroutines, such as RPIPE, RSNGJ and RBRNCH are modified to 

apply the present CCFL correlation to the CCFL model of the modified version, as shown in Fig. 12. 

If one wishes to use the present CCFL correlation, he must specify 2.0 and L/D, for word 2 (form 

selector) and for word 3 (gas intercept) of CCFL data card (ccc1401 •-ccc 1499, for pipe component), 

respectively. The input requirement of the new CCFL model is shown in Table 2. If P3#2.0, the CCFL 

model of the modified version is the same as that of the standard version. 

It is known that the frictional drags and CCFL curve given by user mainly characterize the flooding 

process. If the CCFL by wall friction is more dominant than that by CCFL correlation, flooding occurs 

at lower gas velocity than predicted by the CCFL curve in standard RELAP5. Therefore, digit f of the 

volume control flag in the cell volumes is specified as I so that wall friction effects are not to be 

computed in the test section. 

Table 2. Input Requirement for CCFL Data Card 

Word #1 Word #2 Word #3 Word #4 

Original Input Diameter Form selection ([3) Gas intercept (c) Slope (in) 

Modified Input Diameter 2.0 L/D 0.0 (or slope)

17
SubroutneCCFL 

initialize flags (imph. iskip) 

loop over all junctions

Fig. 11. Flow Chart of the Subroutine CCFL

I8

0 

0 

0 

0:

.-C 

0
Subroutine RPIPIE

3ntce

Fig. 12. Flow Chart of the Modified Subroutine RPIPE 

19
5.2. Comparison of Code Calculation Results by Standard and Modified Versions 

The calculation results by the modified version are compared with those by the standard version. 

It is shown that the present flooding correlation is successfully implemented to standard RELAP5 

in Figs. 13 and 14 where the flooding limits of the empirical correlation are higher or lower than the 

predictions of standard RELAP5, respectively. For a given liquid flow rate, the gas flow rate is 

increased to reach the flooding curve, and then the calculation results of the modified RELAP5 lie 

well on the line given by the empirical correlation. 

In Fig. 13 L/D is such a small value that the standard RELAP5 predicts the higher gas flow than the 

experimental data. In this case, the flooding criterion is satisfied before the interfacial and the wall 

drags initiate CCFL. When L/D is high as shown in Fig. 14, the onset of flooding occurs before the 

flooding limit by the correlation is applied in the RELAP5 calculation. If we set the f digit of the 

volume control flag to 1 in the horizontal test section RELAP5 predictions by the modified version lie 

well on the flooding line as shown in Fig. 14.

20
6

0.04 0.06 0.08 0.10 0.12 0.14 

S*0.5 

if 

Fig. 13. Comparison of Experimental Data with Small L/D 

With Predictions by Standard & Modified RELAP5

• "0.5 

Fig. 14. Comparison of Experimental Data with Large L/D 

With Predictions by Standard & Modified RELAP5

21

0.16

0.55

°
6. Conclusions

A total of 356 experimental data for the onset of flooding are compiled for the data bank and used 

for the assessment of RELAP5/MOD3.2.2 7 predictions of Counter-Current Flow Limitation (CCFL) in 

horizontal-to-inclined pipes simulating a PWR hot leg. From the present study the following 

conclusions can be made. 

I) The dimensionless Wallis-type gas velocities and liquid velocities are identified with the 

geometrical conditions such as horizontal pipe diameter (D), length (L) and the inclination 

angle (0) of the bend. The experimental data show that the flooding curve becomes higher 

with the lower L/D while their 0 effect on CCFL is not found. 

2) The RELAP5 calculations are compared with the experimental data where L/D is varied 

within the range of database. The L/D effect on CCFL is also confirmed in RELAP5 results, 

but higher gas flow rate is required to initiate the flooding compared with the experimental 

data if the LID is as low as that of the hot legs of typical PWRs. 

3) The best fitting correlation is developed for the prediction of flooding points, which shows 

the L/D effect. The present correlation agrees well with the database within the prediction 

error, 8.7%. The result of empirical correlation based on the present data bank is as follows: 

S'0S +0.614jfO = 0.635-0.00254 L). 

4) The present flooding correlation is implemented into the standard RELAP5 and validated 

against the data bank. It is shown that the present flooding correlation is successfully 

implemented to the standard RELAP5 for the both cases where, flooding limit of the 

empirical correlation is higher or lower than the predictions of standard RELAP5.

22
References

1. Richard A. Riemke, "Countercurrent Flow Limitation Model for RELAP5/MOD3", Nuclear 

Technology 93, pp. 166-173, 1991. 

2. Sun Heo, Hee Cheon NO, "Improvement of The CCFL Models of the RELAP5/MOD3.2.2B Code 

in a Horizontal Pipe", Proc. 8th International Conference on Nuclear Engineering, Baltmore, USA, 

2000. 

3. A. Ohnuki, "Experimental Study of Counter-Current Two-Phase Flow in Horizontal Tube 

Connected to Inclined Riser", J. of Nuclear Science and Technology 23 (3), pp. 219-232, 1986. 

4. P.T. Wan, V.S. Krishnan, "Air-Water Flooding in 900 Elbow with a Slightly Inclined Lower Leg", 

Proc. CN 7 th Annual Conf., Toronto, 1986. 

5. H. Siddiqui, S. Banerjee, K.H. Ardron, "Flooding in a Elbow Between a Vertical and a Horizontal 

or Near-Horizontal Pipe", Int. J. Multiphase Flow 12 (4), pp. 531-541, 1986. 

6. M. Kawaji, L.A. Thomson, V.S. Krisnan, "Countercurrent Flooding in Vertical-to-Inclined Pipes", 

Experimental Heat Transfer 4, pp. 95-110, 1991. 

7. S. Wongwises, "Two-Phase Countercurrent Flow in a Model of a Pressurized Water Reactor Hot 

Leg", Nuclear Engineering and Design 166, pp. 121-133, 1996. 

8. S.K. Kang, Hee Cheon NO, "Air-Water Countercurrent Flow Limitation in a Horizontal Pipe 

Connected to an Inclined Riser", J. Korean Nuclear Society 31 (6), pp. 548-560, 1999. 

9. K.Y. Choi, Hee Cheon NO, "Experimental Studies of Flooding in Nearly Horizontal Pipes", Int. J. 

Multiphase Flow 21 (3), pp. 419-436, 1995.

23
Appendix A. Sample Input Deck for CCFL Test
CCFL in horizontal pipe 

* CCFL test input for the Siddiqui's CCFL experiment 

* Test section : D= 47 mm, L= 1820 + 1000 mm(?) 

* Simulation by Hyoung Tae Kim

20543000 jg mult 1.0 

20543001 voidgj 100080000 

20543002 velgt 100080000

h2o t-sec

* TIME STEP CONTROL 

* T end T min T max ssdtt minor major restart 

201 700. I.e-7 0.01 00003 100 10000 10000 

501 time 0 ge null 0 0.0 1 -1.0 

* air injection 

511 time 0 ge null 0 0.0 1 -1.0 

* water injection 

512 time 0 ge null 0 0.0 I -1.0

311 cntrlvar 421 *Wf 

312 cntrlvar 431 *Wg 

316 cntrlvar 428 *jf*1/2 

317 cntrlvar 438 *jg*I/2

20541000 gdrho 

20541001 0.0 

20541002 

20541100 gdrho_ 

20541101 1.0e-4

sum 0.4606 0.0 1 

--- >9.8x0.047 

1.0 rhofJ 100080000 

-1.0 rhogi 100080000

sum 1.0 1.0 1 

1.0 cntrlvar 410

20542000 jf mult 1.0 

20542001 voidfJ 100080000 

20542002 velfJ 100080000

0.0 1

20542100 Wf mult -1.735e-3 

* . .---- > area 

20542101 rhofj 100080000 

20542102 cntrlvar 420

20542200 rf__gdr 

20542201 cntrlvar 

20542202 rhofJ

0.0

div 1.0 0.0 1 

11i 

100080000

20542400 rf._gdr2 powerr 1.0 0.0 1 

20542401 cntrlvar 422 0.5

20542600 jfs mult 

20542601 cntrlvar 420 

20542602 cntrlvar 424 

20542603 cntrlvar 420 

20542604 cntrlvar 424

1.0 0.0 1

20543100 Wg mult 1.735e-3 0.0 1 

* ..----- > area 

20543101 rhogj 100080000 

20543102 cntrlvar 430 

20543200 rggdr div 1.0 0.0 1 

20543201 cntrlvar 411 

20543202 rhogj 100080000 

20543400 rggdr2 powerr 1.0 0.0 1 

20543401 cntrlvar 432 0.5 

20543600 jgs mult 1.0 0.0 1 

20543601 cntrlvar 430 

20543602 cntrlvar 434 

20543603 cntrlvar 430 

20543604 cntrlvar 434 

20543800 jgs2 powerr 1.0 0.0 1 

20543801 cntrlvar 436 0.25 

* hydrodynamic model input for test section 

* Test Section

* component 100: test section 

1000000 test-sec pipe 

1000001 15

1000101 

1000301 

1000302 

1000401 

1000601 

1000602 

1000801 

1000901 

1001001 

1001101 

1001102 

1001103 

1001201 20542800 jfs2 powerr 1.0 0.0 1 

20542801 cntrlvar 426 0.25

01:area, 03:length, 04:volume 

1.735e-3 15 

0.182 10 

0.2 15 

0.0 15

vertical angle 

0.0 

90.0

10 

15

roughness hyd. dia. / energy loss coeff. 

0.0002 0.047 15 

0.0 0.0 14

tlpvbfe / efvcahs 

0000000 15 

0100000 7 

0100000 8 

0100000 14

volume initial condition 

004 1.03e5 293.15 0.0 0.0 0.0 15

A]

100 new transnt 

101 run 

102 si 

105 10. 20. 

110 air 

120 100010000 0.0

0.0 1
* junction initial condition 

1001300 1 

1001301 0.0 00 0.0 14 

* ccfl data card(dia, beta, c, m, no.) 

*1001401 008 0.0 2.0 1.0 

*1001402 0.08 2.0 25.0 0.0 

*1001403 0.08 00 20 1.0

2301001 0000000 

2301101 0000000

3 

4 

7

Left part - air injection & water venting -* ------------ ------ -----------

* component 2 10 : TDV for the air injection 

2100000 air in tmdpvol 

2100101 100 0.0 0-01 0.0 0.0 0.0 

2100102 0.00001 0.0 00

2100200 004 

2100201 0.0 1.03e5 293.15 10

* component 215: TDJ (from 210 to 220) 

2150000 ajun tmdpjun 

2150101 210010000 220000000 :.735e-3 

2150200 1 511 

2150201 -1.0 0.00 0.00 O.CO 

2150202 0.0 0.00 0.00 0.00 

2150203 2000.0 0.00 0.00 0.00 

* component 220: air inlet pipe 

2200000 airin branch 

2200001 1 1 

* area length volume angle(az/inc) elev 

2200101 1.735e-3 05 0.0 0.0 0.0 0.0 

* roughness dia. tlpvbfe 

2200102 0.0002 0.0 010 

2200200 004 1.03e5 293-15 0. ( 

from to are a 

2201101 220010000 230050003 1.735e-3 0.0 0.0 00 

2201201 0.0 0.0 0.0 

* component 230 " water venting tank 

2300000 w-vent pipe 

2300001 5 * 01 ýarea. 03:length 

2300101 0.1 5 

2300301 0.047 2 

2300302 0-047 3 

2300303 0.047 5 

* vertical angle 

2300601 90.0 5 

* roughness hvd. dia./ energy loss coeff.(FW/R) 

2300801 0.0 0.0 5 

2300901 0.0 0.0 4 * tlpvbfe / efvcahs

5 

4

2301201 003 1.03e5 293-15 0.0 0.0 0.0 1 

2301202 004 1.03e5 293.15 0.0 0-0 0.0 3 

2301203 004 1.03e5 293.15 0.0 0.0 0.0 5 

* junction inittial condition 

2301300 1 

2301301 0.0 0.0 0-0 4 

* component 240: single junction (from 230-03 to 100) 

2400000 air-inj sngljun 

* from to area 

2400101 230030003 100000000 1.735e-3 0.0 1.0 00 

2400201 1 0.0 0.0 0.0 

* component 250: TDJ(water out) 

2500000 wtout tmdpjun 

2500101 230000000 260000000 1.8e-2 

2500200 1 501 cntrlvar 421 

2500201 -1.0 0.0 0.00 0.00 

2500202 0.0 0.0 0.00 0.00 

2500203 1.0 1.0 0.00 0.00 

2500204 100.0 100-0 0-00 0-00 

* component 260 : TDV for the water outlet 

2600000 wt out tmdpvol 

2600101 10-0 00 0.01 0.0 0.0 0.0 

2600102 0.00001 0-0 00

2600200 003 

2600201 0.0 1.03e5 293.15

* Right part - water injection & air venting 

---------------- ------------ --- 

* component 310 TDV for the water injection 

3100000 wt in tmdpvol 

3100101 10.0 0.0 0.01 0.0 0-0 0.0 

3100102 0.00001 0.0 00

3100200 003 

3100201 0.0 1.03e5 293-15

* component 315: TDJ (from 310 to 320) 

3150000 w-jun tmdpjun 

3150101 310010000 320000000 1-735e-3 

3150200 I 512 

3150201 -1-0 0.0 0-00 0.00 

3150202 0.0 0.0 0.00 0.00 

3150203 2000-0 0.0 0.00 0.00 

*----------> for the liquid film correction ------

A2
* component 311 : TDV for the water injection 

3110000 wtin tmdpvol 

3110101 10.0 0.0 0.01 0.0 0.0 0.0 

3110102 0.00001 0.0 00 

3110200 003 

3110201 0.0 1.03e5 293.15 

* component 316: TDJ (from 311 to 316) 

3160000 wjun tmdpjun 

3160101 311010000 100100002 1.735e-4 

3160200 1 512 

3160201 -1.0 0.0 0.00 0.00 

3160202 0.0 0.0 0.00 0.00 

3160203 2000.0 0.0 0.00 0.00 

* component 320: water injection line 

3200000 w inj branch 

3200001 1 1 

* area length volume angle(azlinc) elev 

3200101 1.735e-3 0.5 0.0 0.0 0.0 0.0 

* roughness dia. tlpvbfe 

3200102 0.0002 0.0 0000010 

3200200 003 1.03e5 293.15 

* from to area 

3201101 320010000 330000000 1.735e-3 0.0 0.0 00 

3201201 0.0 0.0 0.0 

* component 330: water tank 

3300000 wtnk pipe 

3300001 4 

* 01:area, 03:length, 04:volume 

3300101 0.11 4 

3300301 0.1 4 

3300401 0.0 4 

* verttical angle 

3300601 90.0 4 

* roughness hyd. dia. / energy loss coeff. 

3300801 0.0002 0.0 4 

3300901 0.0 0.0 3 

* tlpvbfe / efvcahs 

3301001 0000000 4 

3301101 0000000 3 

* volume initial condition 

3301201 003 1.03e5 293.15 0.0 0.0 0.0 4 

* junction inittial condition 

3301300 1

3301301 0.0 0.0 0.0 3 

* component 340: right-section 

3400000 right branch 

3400001 3 1 

* area length volume angle(az/inc) elev 

3400101 0.11 0.047 0.0 0.0 90.0 0.047 

* roughness dia. tlpvbfe 

3400102 0.0002 0.0 0000000 

3400200 004 1.03e5 293.15 0.0 

* from to area 

3401101 100010000 340010003 1.735e-3 0.0 0.0 00 

3402101 330010000 340000000 0.11 0.0 0.0 00 

3403101 340010000 350000000 0.11 0.0 0.0 00 

3401201 0.0 0.0 0.0 

3402201 0.0 0.0 0.0 

3403201 0.0 0.0 0.0 

* component 350: air venting pipe 

3500000 air-out pipe 

3500001 4 

* 01:area, 03:length, 04:volume 

3500101 0.11 4 

3560301 0.4 4 

3500401 0.0 4 

* vertical angle 

3500601 90.0 4 

* roughness hyd. dia./ energy loss coeff. 

3500801 0.0002 0.0 4 

3500901 0.0 0.0 3 , 

* tlpvbfe / efvcahs 

3501001 0000000 4 

3501101 0000000 3 , 

* volume initial condition 

3501201 004 1.03e5 293.15 0.0 0.0 0.0 4 

* junction inittial condition 

3501300 1 

3501301 0.0 0.0 0.0 3 

* component 355: single junction (from 350 to 360) 

3550000 air-outj sngljun 

* from to area 

3550101 350010000 360000000 0.002 10.0 0.0 00 

3550201 I 0.0 0.0 0.0 

* component 360 : TDV for the air venting 

3600000 air-tdv tmdpvot 

3600101 10.0 0.0 0.01 0.0 90.0 0.001 

A3
3600102 0.00001 0-0 00 

3600200 004 

3600201 0.0 1.03e5 293.15 0.0 

* MODIFICATION - Water & Air inlection rate 

* TIME STEP CONTROL 

* T end T min T max ssdtt minor major estart 

201 50. l.e-8 0-05 00003 10 6000 6000 

* AIR 

2150203 200.0 0.00 0.008 0.00 

2150204 300.0 0.00 0.008 0.00 

* WATER 

3150201 -1.0 0.00 0.00 0.00 

3150202 0.0 0.00 0.00 0.00 

3150203 10.0 0.0158 0.00 0.00 

3150204 500.0 0.0158 0.00 0.00 

3160202 0.0 0-0158e-2 0000 000 

3160203 10.0 0.0158e-2 0.00 0.00 

End of file 

* water(kg/s) air(kg/s) jf jg 

* 0.0158 0.008 0.117 0.445 

* 0031 0.0065 0.163 0.40 

0.046 0-0052 0-199 0.359 * 0.061 0-0045 0-229 0.333 * 0078 0.0039 0-259 0-311 

S0.093 0.0034 0.283 0-29

A4
Appendix B. Modified parts in the RELAP5 Subroutines
B.1 Subroutine ccfl.f

#79 line 

c Perform preliminary calculations. 

cblh if (iand(ocex(i),4) .eq. 0) go to 1990 

if (.not.isnpccflflg2(2,i)) go to 1990 

cblh

cblh jcex(i) = iand(jcex(i),not(2)) 

cblh

cblh if (iand(jc(i),2).ne.O .or. velfj(i)*velgj(i).ge.O.0) 

cblh * go to 1990 

isccflflgl (2,i) =.false. 

if(istdpjunflg 1 (2,i) .or. velfj(i)*velgj(i) 

& .ge. O.OdO) goto 1990 

k = ij I nx(2,i) 

cblh - -- ----------. . . . . ..

cblh kx = k + iand(ishft(jcex(i),-1 3),3) 

c kx = k + fromface12I4(2,i)I2 

cblh- ------------ 

I = ij2nx(2,i) 

cblh- ---- 

cblh Ix = I + iand(ishft(jcex(i),-10),3) 

c Ix = I + toface911(2,i)12 

cblh

cblh nmapk = iand(imap(kx),63) 

cblh --.-.--.------------------

c nmapk = ismapinfo05(2,kx)

BI
0661 Oý 016 (opo*1 a' lzIOAp~zIOP) A 

l =ap 1zIop (0,"' (8())D ulj

(xI)3zpAq = jzjap

)ja = jfZIOP ((!'Z)ý26IU3Iju3IAwJjJ~eS!)j! 

I-ZioP- = rJZIOP (o'Z]'j7())OuIJ

3lq

(xm)3zpAt4 = )NZOP 

066L ol oB (Z~baedewti jo- Z-baedewu) j! 

(xj'z),sj(ojuidewsi = idewu 

(E9'(x[)di3ui)puu[=iuu qlqz) 

---- ------------------------- qlqz
B.2 Subroutine rpipe.f

#1849 line 

do 609 k =ij,ije,ijskp 

if (diamj(k) Alt. 0.OdO) then 

diamj(k) = 0.OdO 

tfai I .true. 

endif 

c if (betacc(k).It.0.OdO.or. betacc(k).gt. I .OdO) then 

c betacc(k) = 0.OdO 

c tfail = true. 

c endif 

c if (constc(k) .le. 0.OdO) then 

c constc(k) = 0.OdO 

c tfail = .true. 

c endif 

c if (constm(k) .le. O.OdO) then 

c constm(k) = 0.OdO 

c tfail = .true. 

c endif 

if (betacc(k).gt.1 .99 .and. betacc(k).lt.2.01) then 

betacc(k) = 0.0 

if (constc(k) AIt. 2.0 .or. constc(k) .gt. 1000.0) then 

constc(k) = 0.0 

tfail = .true. 

else 

c New CCFL correlation 

constc(k) = 0.635 - 0.00254 * constc(k) 

endif

B3
if (constm(k) ge. 0.0) then 

constm(k)=0.1314 

else 

tfail = .true. 

endif 

else 

if (betacc(k).lt.0.0 .or. betacc(k).gt.1.0) then 

betacc(k) = 0.0 

tfail = .triue. 

endif 

if (constc(k) .ie. 0.0) then 

constc(k) = 0.0 

tfail = .triue. 

endif 

if (constm(k) .le. 0.0) then 

constm(k) = 0.0 

tfail = .true:. 

endif 

endif 

c 

609 continue

B4
Appendix C. Flooding Database
No. Author P D L L/D 0 I .if 0.5 

[MPaJ m] [ir] [m] [m] 

1 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.002 0.722 

2 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.060 0.673 

3 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.087 0.639 

4 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.182 0.590 

5 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.229 0.553 

6 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.304 0.494 

7 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.373 0.448 

8 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.446 0.393 

9 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.540 0.320 

10 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.722 0.205 

11 Ohnuki 0.1 0.026 0.04 1.538 40 0.1 0.002 0.641 

12 Ohnuki 0.1 0.026 0.04 1.538 40 0.1 0.106 0.554 

13 Ohnuki 0.1 0.026 0.04 1.538 40 0.1 0.146 0.519 

14 Ohnuki 0.1 0.026 0.04 1.538 40 0.1 0.237 0.468 

15 Ohnuki 0.1 0.026 0.04 1.538 40 0.1 0.352 0.423 

16 Ohnuki 0.1 0.026 0.04 1.538 40 0.1 0.446 0.363 

17 Ohnuki 0.1 0.026 0.04 1.538 40 0.1 0.573 0.299 

18 Ohnuki 0.1 0.026 0.04 1.538 40 0.1 0.614 0.263 

19 Ohnuki 0.1 0.026 0.04 1.538 40 0.1 0.679 0.185 

20 Ohnuki 0.1 0.026 0.13 5.000 40 0.1 0.001 0.557 

21 Ohnuki 0.1 0.026 0.13 5.000 40 0.1 0.077 0.516 

22 Ohnuki 0.1 0.026 0.13 5.000 40 0.1 0.145 0.463 

23 Ohnuki 0.1 0.026 0.13 5.000 40 0.1 0.247 0.391 

24 Ohnuki 0.1 0.026 0.13 5.000 40 0.1 0.355 0.351 

25 Ohnuki 0.1 0.026 0.13 5.000 40 0.1 0.562 0.215 

26 Ohnuki 0.1 0.026 0.24 9.231 40 0.1 0.001 0.483 

27 Ohnuki 0.1 0.026 0.24 9.231 40 0.1 0.125 0.464 

28 Ohnuki 0.1 0.026 0.24 9.231 40 0.1 0.159 0.433 

29 Ohnuki 0.1 0.026 0.24 9.231 40 0.1 0.187 0.416 

30 Ohnuki 0.1 0.026 0.24 9.231 40 0.1 0.219 0.371 

31 Ohnuki 0.1 0.026 0.24 9.231 40 0.1 0.271 0.343 

32 Ohnuki 0.1 0.026 0.24 9.231 40 0.1 0.315 0.306 

33 Ohnuki 0.1 0.026 0.24 9.231 40 0.1 0.363 0.285 

34 Ohnuki 0.1 0.026 0.24 9.231 40 0.1 0.386 0.249 

35 Ohnuki 0.1 0.026 0.24 9.231 40 0.1 0.450 0.202 

35 Ohnuk~~~~~~~~~~i010060219.31 4 0.10.5 022

36

37 

38 

39 

40

Ohnuki I 0.1

Ohnuki 

Ohnuki 

Ohnuki 

Ohnuki

0.1 

0.1 

0.1 

0.1

0.0261 0.02

0.026 

0.026 

0.026 

0.026

0.02 

0.02 

0.02 

0.02

0.769

0.769 

0.769 

0.769 

-0.76.9

40 

40 

40 

40 

40

0.19 

0.19 

0.19 

0.19 

0.19

0.002 

0.062 

0.089 

0.127 

0.214

0.721 

0.669 

0.635 

0.607 

0.551

Cl
No. Author P D L L/D 5 -'0.5 

EMPa] [m] [in] [m]l [m] if___ J_____ 

41 Ohnuki 0O.1 0 .026 0 .02 0 .769 40 0 .19 0 -301 0- O512 42 Ohnuki -0.1- 0.026 .0.02 0.769 40 0.19 0.414 -- 0.454 

43 Ohnuki 0.1 0.026 0.02 0.769 40 0.19 0.499 0.389 

44 Ohnuki 0.1 0.026 0.02 0.769 40 0.19 0.639 0.323 

45 Ohnuki 0.1 0.026 0.02 0.769 40 0.19 0.785 0.199 

46 Ohnuki 0.1 0.026 0.05 1.923 40 0.19 0.000 0.654 

47 Ohnuki 0.1- 0.026 0.05 1.923 40 0.19 0.083 0.601 

48 Ohnuki 0.1 0.026 0.05 1.923 40 0.19 0.141 0.538 

49 Ohnuki -0.1- 0.026 0.05 1.923 40 0.19 0.198 0.504 

50 Ohnuki 0.1 0.026 0.05 1.923 40 0.19 0.295 0.444 

51 Ohnuki- 0.1 0.026 0.05 1.923 40 0.19 0.451 0.386 

52 Ohnuki- 0.1 0.026 0.05 1,923 40 0.19 0.562 0.390 

53 Ohnuki- 0. 1 0.026 0.05 1.923 40 0.19 0.586 0.-312

54 Ohnuki 0.1 0.026 10.05 1.923 40 0.19 0.713 0.195 

55 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.000 0.621 

56 Ohnuki -0.1 0.026 0.08 3.077 -- 40 0.19 0.078 0.559,-

57 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.133 0.522 

58 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.246 0.464 

59 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.309 0.402 

60 Ohnuki .0.1- 0.026 0.08 3.077 40 0.19 0.518 0.330. 

61 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 10.740 0.217 

62 Ohnuki 0.1 0.026 0.19 7.308 40 0.05 0.000 0.483 

63 Ohnuki 0.1 0.026 0.19 7.308 40 0.05 0.056 0.453 

64 Ohnuki 0.1 0.026 0.19 7.308 40 0.05 0.089 0.423 

-65 Ohnuki -0.1 0.026 0.19 -7.308 40 0.05 0.136 -0.393 

66 Ohnuki 0.1 0.026 0.19 7.308 40 0.05 0.207 0.349 

67 Ohnuki- 0.1 0.026 0.19 7.308 40 -0.05 0.261 0.-3 115 

68 Ohnuki 0.1 0.026 0.19 7.308 40 0.05 0.306 0.286 

69 Ohnuki 0.1 0.026 0.19 7.308 40 0.05 0.440 0.198 

-70 Ohnuki. 0. 1 0.026 0.01 0.385 40 0.1 0.000 ý0.822 

71 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.048 0.718 

72 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.088 0-673 

73 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.131 0 .643 

74 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.191 0.617 

75 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.281 0.568 

76 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.358 0.524 

77 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.470 0.457 

78 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.644 0.326 

79 Ohnuki 0.1 0.026 0.01 0.385 40 0.1 0.723 0.207 

80 Ohnukio0.1 0.026 ,0.01 0.385 40 0.1 0.545 0.390

C2
No. Author P D L L/D '05j 

[MPa [m] [m] [m] [m] if 

81 Ohnuki 0.1 0.026 0.19 7.308 40 0.05 0.000 0.559 

82 Ohnuki 0.1 0.026 0.19 7.308 40 0.05 0.065 0.514 

83 Ohnuki 0.1 0.026 0.19 7.308 40 0.05 0.195 0.451 

84 Ohnuki 0.1 0.026 0.19 7.308 40 0.05 0.231 0.388 

85 Ohnuki 0.1 0.026 0.19 7.308 40 0.05 0.323 0.318 

86 Ohnuki 0.1 0.026 0.19 7.308 40 0.05 0.460 0.196 

87 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.005 0.611 

88 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.051 0.561 

89 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.071 0.534 

90 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.128 0.501 

91 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.222 0.453 

92 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.284 0.394 

93 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.457 0.322 

94 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.648 0.292 

95 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.793 0.214 

96 Ohnuki 0.1 0.051 0.3 5.882 45 0.6 0.001 0.720 

97 Ohnuki 0.1 0.051 0.3 5.882 45 0.6 0.043 0.658 

98 Ohnuki 0.1 0.051 0.3 5.882 45 0.6 0.125 0.591 

99 Ohnuki 0.1 0.051 0.3 5.882 45 0.6 0.211 0.508 

100 Ohnuki 0.1 0.051 0.3 5.882 45 0.6 0.050 0.676 

101 Ohnuki 0.1 0.051 0.3 5.882 45 0.6 0.128 0.611 

102 Ohnuki 0.1 0.051 0.3 5.882 45 0.6 0.188 0.530 

103 Ohnuki 0.1 0.051 0.3 5.882 45 0.6 0.235 0.496 

104 Ohnuki 0.1 0.051 0.3 5.882 45 0.6 0.316 0.449 

105 Ohnuki 0.1 0.076 0.4 5.263 45 0.6 0.000 0.716 

106 Ohnuki 0.1 0.076 0.4 5.263 45 0.6 0.032 0.663 

107 Ohnuki 0.1 0.076 0.4 5.263 45 0.6 0.081 0.634 

108 Ohnuki 0.1 0.076 0.4 5.263 45 0.6 0.113 0.609 

109 Ohnuki 0.1 0.076 0.4 5.263 45 0.6 0.156 0.581 

110 Ohnuki 0.1 0.076 0.4 5.263 45 0.6 0.197 0.554 

1i1 Ohnuki 0.1 0.076 0.4 5.263 45 0.6 0.226 0.524 

112 Ohnuki 0.1 0.076 0.4 5.263 45 0.6 0.261 0.501 

113 Ohnuki 0.1 0.076 0.4 5.263 45 0.6 0.307 0.468

114 

115 

116 

117 

118 

119 

120

Ohnuki 0.1

Ohnuki 

Ohnuki 

Ohnuki 

Ohnuki 

Ohn~uki 

Ohnuk

0.1 

0.1 

0.1 

0.1 

0.1

0.076 1 0.4 1 5.263

0.076 

0.076 

0.076 

0.076 

0.076 

0.076

0.4 

0.4 

0.4 

0.4 

0.4 

0.4

5.263 

5.263 

5.263 

5.263 

5.263 

5.263

45 +-

45 

45 

45 

45 

45 

45

0.6 0.006 0.700

0.6 

0.6 

0.6 

0.6 

0.6 

0.6

0.037 

0.079 

0.123 

0.149 

0.192 

0.245

0.690 

0.661 

0.632 

0.609 

0.576 

0.545

C3
No- Author P D L L/D .05 -*0.5 

_MPa] [m ] [m ] [m] Em] _ 

121 Ohnuki 01 0.076 0.4 5.263 45 0.6 0.271 0.517 

122 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.003 0.651 

123 :Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.106 0.562 

124 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.174 0.523 

125 ! Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.304 0.464 

126 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.335 0.405 

127 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.521 0.332 

128 Ohnuki 0.1 0.026 0.08 3.077 40 0.19 0.732 0.209 

129 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.000 0.522 

130 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.074 0.492 

131 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.113 0.442 

132 Ohnuki 0.1 0.026 0.19 7.308 40 0,038 0.133 0.423 

133 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.173 0.382 

134 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.228 0.343 

135 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.264 0.310 

136 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.294 0.277 

137 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.478 0.194 

138 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.002 0.541 

S139 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.066 0.483 P 140 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.130 0.443 

141 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.145 0.423 

142 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.212 0.390 

143 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.247 0.343 

144 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.277 0.30 

145 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.308 0.281 

146 Ohnuki 0.1 0.026 0.19 7.308 40 0.038 0.422 0.193 

147 Wan 0.051 2.958 58 90 0.201 0.378 

148 Wan 0.051 2.958 58 90 0.252 0.351 

149 Wan 0.051 2.958 58 90 0.262 0.337 

1 50 Wan 0.051 2.958 58 90 0.273 0.337 

151 Wan 0.051 2.958 58 90 0.278 0.326 

152 Wan 0.051 2-958 58 90 0.373 0.271 

153 Wan 0.051 2.958 58 90 0.384 0.268 

154 Wan 0.051 2.958 58 90 0.453 0.226 

155 Wan 0.051 2.958 58 90 0.459 0.217

1 56 

157 

1 58 

159 

160

Wan 

Wan 

Wan 

Wan 

Wan

0.051 

0.051 

0.051 

0.051 

0.051

2.958 

2.958 

2.958 

2.958 

2.958

58 

58 

58 

58 

58 

C4

91 

91 

91 

91 

91

0.212 

0.242 

0-292 

0-332 

0.373

0.341 

0.330 

0.301 

0.262 

0.243
No. Author P D 1 L/D I Jf°05 ]g.o 

[MPa] [ml [m] [ml [m] 

161 Wan 0.051 2.958 58 91 0.423 0.213 

162 Wan 0.051 2.958 58 91 0.510 0.162 

163 Wan 0.051 2.958 58 91 0.519 0.142 

164 Wan 0.051 2.958 58 91 0.568 0.127 

165 Siddiqui 0.1 0.038 2.36 62.1053 90 0.147 0.384 

166 Siddiqui 0.1 0.038 2.36 62.1053 90 0.165 0.386 

167 Siddiqui 0.1 0.038 2.36 62.1053 90 0.190 0.368 

168 Siddiqui 0.1 0.038 2.36 62.1053 90 0.267 0.325 

169 Siddiqui 0.1 0.038 2.36 62.1053 90 0.300 0.296 

170 Siddiqui 0.1 0.038 2.36 62.1053 90 0.342 0.280 

171 Siddiqui 0.1 0.038 2.36 62.1053 90 0.355 0.255 

172 Siddiqui 0.1 0.044 2.24 50.9091 90 0.123 0.422 

173 Siddiqui 0.1 0.044 2.24 50.9091 90 0.174 0.390 

174 Siddiqui 0.1 0.044 2.24 50.9091 90 0.214 0.355 

175 Siddiqui 0.1 0.044 2.24 50.9091 90 0.245 0.347 

176 Siddiqui 0.1 0.044 2.24 50.9091 90 0.247 0.332 

177 Siddiqui 0.1 0.044 2.24 50.9091 90 0.301 0.313 

178 Siddiqui 0.1 0.044 2.24 50.9091 90 0.301 0.301 

179 Siddiqui 0.1 0.044 2.24 50.9091 90 0.348 0.283 

180 Siddiqui 0.1 0.044 2.24 50.9091 90 0.390 0.268 

181 Siddiqui 0.1 0.044 2.24 50.9091 90 0.391 0.247 

182 Siddiqui 0.1 0.044 2.24 50.9091 90 0.415 0.255 

183 Siddiqui 0.1 0.044 2.24 50.9091 90 0.429 0.245 

184 Siddiqui 0.1 0.044 .2.24 50.9091 90 0.447 0.235 

185 Siddiqui 0.1 0.044 2.1 47.7273 90 0.123 0.375 

186 Siddiqui 0.1 0.044 2.1 47.7273 90 0.193 0.342 

187 Siddiqui 0.1 0.044 2.1 47.7273 90 0.222 0.323 

188 Siddiqui 0.1 0.044 2.1 47.7273 90 0.248 0.305 

189 Siddiqui 0.1 0.044 2.1 47.7273 90 0.304 0.274 

190 Siddiqui 0.1 0.047 1.82 38.7234 90 0.115 0.445 

191 Siddiqul 0.1 0.047 1.82 38.7234 90 0.162 0.415 192 Siddiqui 0.1 0.047 1.82 38.7234 90 0.198 0.397 

193 Siddiqui 0.1 0.047 1.82 38.7234 90 0.197 0.388 

194 Siddiqui 0.1 0.047 1.82 38.7234 90 0.228 0.361 

195 Siddiqui 0.1 0.047 1.82 38.7234 90 0.257 0.339 

196 Siddiqui 0.1 0.047 1.82 38.7234 90 0.281 0.328

197 

198 

199

Ka~waj-i

Kawaji 

Kawaji

0.1 

0.1 

0.1

0.051 

0.051 

0.051

2.54 

2.54 

2.54

49.8039 

49.8039 

49.8039

90 

90 

90

1 

1 

1

0.216 

0.251 

0.301

0.386 

0.362 

0.324

C5
No. Author P D L L/D I 0 5 *0 

[MPa] [m] [m] [m] [m] 

201 Kawaji 0.1 0.051 2.54 49-8039 90 1 0.365 0.280 

202 Kawaji 0.1 0-051 2-54 49.8039 90 1 0.422 0.249 

203 Kawap 0.1 0.051 2.54 49.8039 90 1 0.470 0.236 

204 UF 1.5 0.75 7.086 9.448 50 1.186 0.025 0.642 

205 UPTE 1.5 0.75 7.086 9.448 50 1.186 0.032 0.607 

206 UPTF 1.5 0.75 7.086 9.448 50 1.186 0.045 0.588 

207 UPTF 1.5 0.75 7.086 9.448 50 1.186 0.050 0.582 

208 UPTF 1.5 0.75 7.086 9.448 50 1.186 0.072 0.569 

209 UPTF 1.5 0.75 7.086 9.448 50 1.186 0.117 0.538 

210 UPTF 1.5 0.75 7.086 9.448 50 1.186 0.156 0.499 

211 MHYRESA 0.1 0.351 2.645 7-536 50 1.06 0.000 0.616 

212 MHYRESA 0.1 0.351 2.645 7.536 50 1.06 0.024 0.602 

213 MHYRESA 0.1 0.351 2.645 7.536 50 1.06 0.037 0.590 

214 MHYRESA 0.1 0.351 2.645 7.536 50 1.06 0.052 0.578 

215 MHYRESA 0.1 0.351 2.645 7.536 50 1.06 0.075 0.568 

216 MHYRESA 0.1 0.351 2.645 7.536 50 1.06 0.101 0.554 

217 MHYRESA 0.1 0.351 2.645 7.536 50 1.06 0.128 0.541 

218 MHYRESA 0.1 0.351 2.645 7.536 50 1.06 0.150 0.531 

219 MHYRESA 0.1 0.351 2.645 7.536 50 1.06 0.178 0.516 

220 Wongwises 2.13 0.064 1.408 22 75 1.3 0.064 0.555 

221 Wongwises :2.13 0.064 1.408 22 75 1.3 0.088 0.540 

222 Wongwises 2.13 0.064 1.408 22 75 1.3 0.107 0.524 

223 Wongwises ).13 0.064 1.408 22 75 1.3 0.116 0.503 

224 0.13 0.064 1.408 22 75 1.3 0.123 0.514 

225 Wongwises '.13 0.064 1.408 22 75 1.3 0.135 0.505 

226 Wongwises '.13 0.064 1.408 22 75 1.3 0.146 0.503 

227 Wongwises '2.13 0.064 1,408 22 75 1.3 0.156 0.505 

228 Wongwises 2.13 0.064 1-408 22 75 1.3 0.166 0.498 

229 Wongwises 2.13 0.064 1.408 22 50 1.3 0.064 0.548 

230 Wongwisesý 2.13 0.064 1.408 22 50 1.3 0.077 0.558 

231 Wo.gwises 2.13 0.064 1,408 22 50 1.3 0.088 0.541 

232 Wongwises 0.13 0.064 1.408 22 50 1.3 0.098 0.542 

233 Wongwises 2.13 0.064 1.408 22 50 1.3 0.106 0.534 

234 Wongwises 0.13 0.064 1.408 22 50 1.3 0.116 0.532 

235 Wongwises 2.13 0.064 1.408 22 50 1.3 0.135 0.525 

236 Wongwises ).13 0.064 1.408 22 50 1.3 0.140 0.525 

237 Wongwises (.13 0.064 1.408 22 50 1.3 0.146 0.524 

238 Wongwises 1.13 0.064 1.408 22 50 1.3 0.166 0.517

239 

240

Wongwises 

Wongwises

(2.13 

(0.13

0.064 

0.064

1 .408 

1 .408

22 

22

50 

50

1.3 

1 .3

0.063 

0.064

0.540 

0.565

C6
.*0.5 .*0.5 

No. Author P. D L L/D 0 J]" is 5 

[MPa] [m] [m] [m] [im] 

241 Wongwises 0.13 0.064 1.408 22 50 1.3 0.071 0.534 

242 Wonowises 0.13 0.064 1.408 22 50 1.3 0.077 0.531 

243 Wongwises 0.13 0.064 1.408 22 50 1.3 0.081 0.551 

244 Wongwises 0.13 0.064 1.408 22 50 1.3 0.088 0.524 

245 Wongwises 0.13 0.064 1.408 22 50 1.3 0.091 0.522 

246 Wongwises 0.13 0.064 1.408 22 50 1.3 0.093 0.525 

247 Wongwses 0.13 0.064 1.408 22 50 1.3 0.099 0.528 

248 Wongwises 0.13 0.064 1.408 22 50 1.3 0.107 0.541 

249 Wongwises 0.13 0.064 1.408 22 50 1.3 0.107 0.524 

250 Wongwises 0.13 0.064 1.408 22 50 1.3 0.112 0.533 

251 Wongwises 0.13 0.064 1.408 22 50 1.3 0.117 0.520 

252 Wongwises 0.13 0.064 1.408 22 50 1.3 0.123 0.507 

253 Wongwises 0.13 0.064 1.408 22 50 1.3 0.126 0.511 

254 Wongwises 0.13 0.064 1.408 22 50 1.3 0.129 0.523 

255 Wongwises 0.13 0.064 1.408 22 50 1.3 0.130 0.512 

256 Wongwises 0.13 0.064 1.408 22 50 1.3 0.135 0.506 

257 Wongwises 0.13 0.064 1.408 22 50 1.3 0.140 0.498 

258 Wongwises 0.13 0.064 1.408 22 50 1.3 0.146 0.497 

259 Wongwises 0.13 0.064 1.408 22 50 1 .3 0.151 0.490 

260 Wongwises 0.13 0.064 1.408 22 90 1 .3 0.072 0.538 

261 Wongwises 0.13 0.064 1.408 22 90 1.3 0.083 0.530 

262 Wongwises 0.13 0.064 1.408 22 90 1.3 0.104 0.516 

263 Wongwises 0.13 0.064 1.408 22 90 1.3 0.118 0.506 

264 Wongwises 0.13 0.064 1.408 22 90 1.3 0.137 0.502 

265 Wongwises 0.13 0.064 1.408 22 90 1.3 0.148 0.490 

266 Wongwises 0.13 0.064 1.408 22 90 1.3 0.158 0.490 

267 Wongwises 0.13 0.064 1.408 22 90 1.3 0.168 0.483 

268 Wonowises 0.13 0.064 1.408 22 90 1.3 0.190 0.480 

269 Wongwises 0.13 0.064 1.408 22 90 1.3 0.066 0.558 

270 Wongwises 0.13 0.064 1.408 22 90 1.3 0.090 0.527 

271 Wongwises 0.13 0.064 1.408 22 90 1.3 0.091 0.544 

272 Wongwises 0.13 0.064 1.408 22 90 1.3 0.109 0.531 

273 Wongwises 0.13 0.064 1.408 22 90 1.3 0.125 0.513 

274 Wongwises 0.13 0.064 1.408 22 90 1.3 0.127 0.513 

275 Wongwises 0.13 0.064 1.408 22 90 1.3 0.134 0.515 

276 Wongwises 0.13 0.064 1.408 22 90 1.3 0.137 0.504 

277 Wongwises 0.13 0.064 1.408 22 90 1.3 0.153 0.495 

278 Wongwises 0.13 0.064 1.408 22 90 1.3 0.177 0.486

279 

280

0.13 

0.13

0.064 

0.064

0.557 

0.557

8.7

8.7

50 

50

1.3 

1 .3

0.064 

0.065

0.581 

0.573

C7

Wongwises 

Wongwises
No. Author P D L LID -o 

[MPa] I[m]3 [m] [m] [m] 

281 WongWiSE 0.13 0.064 0.557 8.7 50 1,3 0.078 0.572 

282 WonQWISEýS 0,13 0.064 0-557 8.7 50 1.3 0.090 0.566 

283 WongWISEt 0-13 0.064 0.557 8.7 50 1.3 0.099 0.567 

284 WongWiSES 0.13 0.064 0.557 8.7 50 1.3 0.101 0.567 

285 WonQWiSES 0.13 0.064 0.557 8.7 50 1.3 0.109 0.557 

286 WongWISES 0.13 0.064 0.557 8.7 50 1.3 0.112 0.560 

287 WongWiSEs 0.13 0.064 0.557 8.7 50 1.3 0.113 0.560 

288 WongWISES 0.13 0.064 0.557 8.7 50 1.3 0.117 0.559 

289 WongWISES 0.13 0.064 0.557 8.7 50 1.3 0.122 0.560 

290 Wongwses 0,13 0.064 0.557 8.7 50 1.3 0.123 0.559 

291 Wongwises 0.13 0.064 0.557 8.7 50 1.3 0.126 0.551 

292 Wongwises 0.13 0.064 0.557 8.7 50 1.3 0.132 0.550 

293 Wongwlses 0.13 0.064 0.557 8.7 50 1.3 0.134 0.552 

294 Wongwises 0.13 0.064 0.557 8.7 50 1.3 0.137 0.550 

295 Wongwises 0.13 0.064 0.832 13 50 1.3 0.058 0.583 

296 Wongwses 0.13 0.064 0.832 13 50 1.3 0.063 0.565 

297 Wongwises 0.13 0.064 0.832 13 50 1.3 0.066 0.581 

298 Wongwises 0.13 0.064 0.832 13 50 1.3 0.071 0.575 

299 WongwweS 0.13 0.064 0.832 13 50 1.3 0.077 0.550 

300 Wongwises 0.13 0.064 0.832 13 50 1.3 0.081 0.553 

301 Wongwises 0.13 0.064 0.832 13 50 1.3 0.091 0.559 

302 Wongwises 0.13 0.064 0.832 13 50 1.3 0.096 0.550 

303 Wongwises 0.13 0.064 0.832 13 50 1.3 0.101 0.533 

304 Wongwises 0.13 0.064 0.832 13 50 1.3 0.108 0.529 

305 Wongwises 0.13 0.064 0.832 13 50 1.3 0.110 0.537 

306 Wongwises 0.13 0.064 0.832 13 50 1.3 0.114 0.539 

307 Wongwisez 0.13 0.064 0.832 13 50 1.3 0.121 0.535 

308 Wongwises 0.13 0.064 0.832 13 50 1.3 0.125 0.541 

309 Wongwises 0.13 0.064 0.832 13 50 1.3 0.123 0.516 

310 Wongwises 0.13 0.064 0.832 13 50 1.3 0.125 0.523 

311 Wongwises 0.13 0.064 0.832 13 50 1.3 0.130 0.518 

312 Won0wiseti0.13 0.064 0.832 13 50 1.3 0.134 0.516 

313 Wongwises 0.13 0.064 0.832 13 50 1.3 0.138 0.515

314 

315 

316 

31 7 

318 

319 

320

Wongwises 

Wongwises 

Wongwises 

Wongwises 

Wongwises 

Wongwises 

Wongwises

0.13 

0.13 

0.13 

0.13 

0.13 

0.13 

0.13

0.064 

0.064 

0.064 

0.064 

0.064 

0.064 

0.064

1 .408 

1.408 

1 .408 

1 .408 

1 .408 

1 .408 

1.408

22 

22 

22 

22 

22 

22 

22

75 

75 

75 

75 

75 

75 

75

1 .3 

1 .3 

1 .3 

1 .3 

1 .3 

1 .3 

1 .3

0.065 

0.077 

0.088 

0.107 

0.116 

0.135 

0.146

0.537 

0.539 

0.511 

0.521 

0.518 

0.493 

0.503

C8
-*0.5 -*0.5 

No. Author P D L LID 0 I / ig 

[MPa] [m] [m] [m] [m] 

321 Wongwises 0.13 0.064 1.408 22 75 1.3 0.156 0.493 

322 Wongwises 0.13 0.064 1.408 22 75 1.3 0.166 0.493 

323 lWongwises 0.13 0.064 1.408 22 75 1.3 0.176 0.476 

324 KAIST 0.1 0.08 3.388 42.35 35 0.623 0.000 0.511 

325 KAIST 0.1 0.08 3.388 42.35 35 0.623 0.071 0.501 

326 KAIST 0.1 0.08 3.388 42.35 35 0.623 0.106 0.487 

327 KAIST 0.1 0.08 3.388 42.35 35 0.623 0.149 0.470 

328 KAIST 0.1 0.08 .3.388 42.35 35 0.623 0.201 0.443 

329 KAIST 0.1 0.08 3.388 42.35 35 0.623 0.254 0.424 

330 KAIST 0.1 0.08 3.388 42.35 35 0.623 0.302 0.416 

331 KAIST 0.1 0.08 2 25 35 0.623 0.000 0.524 

332 KAIST 0.1 0.08 2 25 35 0.623 0.066 0.505 

333 KAIST 0.1 0.08 2 25 35 0.623 0.100 0.502 

334 KAIST 0.1 0.08 2 25 35 0.623 0.151 0.476 

335 KAIST 0.1 0.08 2 25 35 0.623 0.202 0.456 

336 KAIST 0.1 0.08 0.928 11.6 35 0.623 0.000 0.587 

337 KAIST 0.1 0.08 0.928 11.6 35 0.623 0.071 0.540 

338 KAIST 0.1 0.08 0.928 11.6 35 0.623 0.104 0.527 

339 KAIST 0.1 0.08 0.928 11.6 35 0.623 0.151 0.521 

340 KAIST 0.1 0.08 0.49 6.125 35 0.623 0.000 0.601 

341 KAIST 0.1 0.08 0.49 6.125 35 0.623 0.077 0.551 

342 KAIST 0.1 0.08 0.49 6.125 35 0.623 0.109 0.540 

343 KAIST 0.1 0.04 3.388 84.7 35 0.648 0.000 0.406 

344 KAIST 0.1 0.04 3.388 84.7 35 0.648 0.165 0.335 

345 KAIST 0.1 0.04 3.388 84.7 35 0.648 0.195 0.312 

346 KAIST 0.1 0.04 3.388 84.7 35 0.648 0.255 0.312 

347 KAIST 0.1 0.04 3.388 84.7 35 0.648 0.294 0.287 

348 KAIST 0.1 0.04 3.388 84.7 35 0.648 0.351 0.259 

349 KAIST 0.1 0.04 3.388 84.7 35 0.648 0.395 0.228 

350 KAIST 0.1 0.04 1 25 35 0.648 0.000 0.549 

351 KAIST 0.1 0.04 1 25 35 0.648 0.164 0.513 

352 KAIST 0.1 0.04 1 25 35 0.648 0.198 0.482 

353 KAIST 0.1 0.04 1 25 35 0.648 0.260 0.433 

354 KAIST 0.1 0.04 1 25 35 0.648 0.286 0.433 

355 KAIST 0.1 0.04 0.7 17.5 35 0.648 0.000 0.573 

356 KAIST 0.1 0.04 0.7 17.5 35 0.648 0.166 0.511

C9
NRC FORM 335 U.S. NUCLEAR REGULATORY COMMISSION 1. REPORT NUMBER 

(2-89) (Assigned by NRC, Add VoL., Supp, Rev., NRCM 1102, DATA SHEET and Addendum Numbers, If any.) 

(See instructions on the reverse) 

2. TITLE AND SUBTITLE NUREG/IA-0203 

Assessment of RELAP5/MOD3.2.2 Against Flooding Database in 3. DATE REPORT PUBLISHED 

Horizontal-to-Inclined Pipes MODTE MONTH [ YEAR 

July 2001 

4. FIN OR GRANT NUMBER 

5. AUTHOR(S) 6. TYPE OF REPORT 

H.T. Kim, H.C. No, KAIST Technical 

S.J. Ha, N.S Ahn, KEPRI 

Y.S. Bang, KINS 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.) 

Korea Advanced Institute of Science and Technology, 373-1, Gusung-Dong, Yusung-Ku, Taejon 305-701 Korea 

Korea Electric Power Research Institute, 103-16 Munji-Dong, Yusung-Ku, Taejon 305-380 Korea 

Korea Institute of Nuclear Safety, PO Box 114, Yuseong-Gu, Taejon 305-600 Korea

9. SPONSORING ORGANIZATION - NAME AND ADDRESS (If NRC, Wye 'Same as above; ff contractor, provide NRC Division, Offce or Region, U.S. Nuclear Regulatory Commission, 

and mailing address.) 

Division of System Analysis and Regulatory Effectiveness 

Office of Nuclear Regulatory Research 

U.S. Nuclear Regulatory Commission 

Washington, DC 20555-0001 

10. SUPPLEMENTARY NOTES

11. ABSTRACT (200 words or less) 

A total of 356 experimental data for the onset of flooding are compiled for the data bank and used for the assessment of 

RELAP5/MOD3.2.2 predictions of Counter-Current Flow Limitation (CCFL) in horizontal-to-inclined pipes simulating a PWR hot 

leg. RELAP5 calculations show that higher gas flow rates are required to initiate the flooding compared with the experimental 

data if the L/D is low as that of the hot legs of typical PWRs. Based on the present data bank, the new CCFL correlation is 

derived, which shows the L/D effect. The present correlation agrees well with the database within the prediction error, 8.7% and 

it is implemented into the RELAP5 and validation against the data bank. The predictions of the flooding limit by the modified 

version lie well on the applied CCFL curve even if the predictions by standard RELAP5 are lower than the present CCFL curve.

12. KEY WORDSIDESCRIPTORS (List words or phrases that will assist researchers in locating the report.) 13. AVAILABILITY STATEMENT 

RELAP5 unlimited 

Flooding 14. SECURITY CLASSIFICATION 

CCFL (This Page) 

unclassified 

(This Report) 

unclassified 

15. NUMBER OF PAGES 

16. PRICE

NRC FORM 335 (2-89)
Federal Recycling Program
N U REG/I A-0203 ASSESSMENT OF RELAP5/MOD3.2.2y AGAINST FLOODING DATABASE IN 

IIORIZONI'AL-TO-IN(LINEI) PIPES

UNITED STATES 

NUCLEAR REGULATORY COMMISSION 

WASHINGTON, DC 20555-0001 

OFFICIAL BUSINESS 

PENALTY FOR PRIVATE USE, $300

JUIY 2001