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NIST Technical Note 1282

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NIST Technical Note 1282

Refinement of a Model for

Fire Growth and Smoke Transport

Walter W. Jones

Center for Fire Research

National Engineering Laboratory

National Institute of Standards and Technology

Gaithersburg, MD 20899

November 1990

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U.S. Department o! Commerce

Robert A. Mosbacher, Secretary

National Institute of Standards and Technology

John W. Lyons, Director
National Institute of Standards U.S. Government Printing Office For sale by the Superintendent

and Technology Washington: 1990 of Documents

Technical Note 1282 U.S. Government Printing Office

Natl. Inst. Stand. Technol. Washington, DC 20402

Tech. Note 1282

50 pages (Nov. 1990)

CODEN: NTNOEF
CONTENTS

1. INTRODUCTION 1

2. SOURCE TERMS 4

2.1 Hydrogen Chloride Deposition 4

2.2 Chemistry 6

2.3 Mechanical Ventilation 9

3. SOURCE MODULES 13

3.1 Hydrogen Chloride Deposition 13

3.2 Chemistry 15

3.3 Mechanical Ventilation 18

4. DESCRIPTION OF THE DATA FILE USED BY FAST 26

5. EXAMPLE OF HYDROGEN CHLORIDE DEPOSITION AND MECHANICAL

VENTILATION 31*

6. ERRATA for "Technical Reference Guide for FAST Version 18" 34

7. NOMENCLATURE 36

8. REVISION HISTORY 38

9. REFERENCES 45

10. ACKNOWLEDGMENTS 46

LIST OF FIGURES

Figure 1. Fraction, (1.0-EXP(-10.0*O2INDEX)), as a function of oxygen and its limiting index. 17

Figure 2. Node arrangement for example 2 29

Figure 3. Plan diagram of the geometry used in the HCl deposition calculation 32

Figure 4. HCL concentration in the lower layer of compartments 2 and 3 33

HI
THIS PAGE INTENTIONALLY LEFT BLANK

IV
Refinement of a Model for Fire Growth and Smoke Transport

Walter W. Jones

Center for Fire Research

National Institute of Standards and Technology

This document describes the changes which have occurred in FAST, FASTplot, FASTJn and the

distribution disks in the change from 18.3, the release for Hazard I, and the current release 18.5. Included

are an errata section for the Technical Note 1262, a revision history that is distributed with the release

disks, the addendum to the Technical Note for the new key words, and the description of the implementation of the physical routines.

Key words: compartment fires; fire growth; mathematical models; numerical models; room fires; smoke; toxicity

1. INTRODUCTION

This report describes additional features in the FAST model, and corrections to the

Technical Reference Guide for FAST [1]. In addition, in the appendix there is a list of the

revision history for this version of the model. This publication is not intended to stand alone.

A presumption is made that the reader is familiar with FAST, the technical publications which

describe the underpinnings, and the Technical Reference Guide.

The original Technical Reference Guide described the basis of the model, the data file used by the model, and described the ancillary modules which are used in conjunction with the

model to provide a complete system for modeling fire growth and smoke spread. Since that

publication, several algorithms have been added, and the purpose of this report is to document them. We have attempted to use a style similar to the earlier work.

Two phenomena which have been added are forced ventilation and deposition of

hydrogen chloride on material surfaces. Also, a more general chemistry scheme is now

included which allows for oxygen and chlorine in the fuel. There have also been a series of

imtprovements and fixes in the software. These latter are documented in the section on the

revision history. Mechanical ventilation was added in a manner similar to conduction of heat

through surfaces and objects, and it will be described as a normal source term. The

mechanical ventilation is based on a large body of knowledge and experience which is derived
Refinement of a Model for Fire Growth and Smoke Transport

from the extensive work on development of heating, ventilation and airconditioning systems.

Likewise, the hydrogen chloride work is based on standard experimental techniques, but the

actual number of such measurements is small. Thus data exist only for a few materials.

We have used the concept of time splitting in several places. With this concept, we

can break out the phenomena which occur on widely varying times scales and solve them

separately. We have used this concept in several places throughout the numerical

implementation of FAST. For example, the time scale for a chemical reaction is normally

much shorter than the time associated with gas flow, namely the number of air changes per

hour in a compartment. This is reasonable in that typical kinetic time scales are on the order

of milliseconds, whereas volumetric changes due to flow are on the order of tenths of seconds.

It is certainly possible to violate these precepts. For example, we are precluded from

modeling detonation. For a fan system, there is an implicit assumption that the inertia in the

system, and the friction in the duct work will cause a significant delay between a pressure rise in a compartment and the effects on the ventilation system. The time step appropriate to this concept is 0.1 s, at least for this model. On such a time scale, wall temperatures will not

change appreciably, and flow in ducts will not be altered very much.

In keeping with the original work, this document first describes the basis for the added

phenomena and the equations which are used by the model. The second section is an annotated listing of the software used to implement these equations. The third section

describes the changes in the data file as used by the "core" model. Finally, an example is shown which emphasizes the new features.

We have changed or added three features of the model: the chemistry, mechanical

ventilation and the dynamics of a gas-surface interaction. These three phenomena represent

extremes in phenomenology of modeling in general:

The chemistry algorithm results simply from a molecular balance. As such

there is no assumption, nor any approximations. We have ignored species

which are truly minor, such as argon. Also, the most difficult aspect of fire related kinetics has not been addressed in this implementation. The carbon

monoxide-carbon dioxide ratio has been left as a parameter. It is incorporated

in such a way that converting to an explicit scheme is easy, but as yet, there is not sufficient knowledge to do this.

For the mechanical ventilation, the formulae come from well established

practice with ventilation systems. We have instantiated an ability to calculate

ventilation much more precisely than measurements are made.

Finally, the wall deposition phenomena present in the hydrogen chloride

algorithm has been established with only a few measurements. More

experimental work needs to be performed to establish confidence in the

coefficients, and indeed to established these coefficients for a wide range of

materials.
Introduction

One fact has become apparent. It is that we are able to predict, run parameter studies

and so on much more readily and widely than can be calibrated experimentally. Indeed, one

of the seductive features of such a model, is that it is possible to perform calculations for

situations for which measurements are not practical. Thus validation of the various parts of

the model is extremely important.
Refinement of a Model for Fire Growth and Smoke Transport

2. SOURCE TERMS

The conserved quantities, pressure, mass, etc., in each compartment are described by

the set of predictive equations discussed by Jones [2] and Jones and Peacock [1]. The form

of the equations is such that the physical phenomena are source terms on the right-hand-side

of these equations. Such a formulation makes the addition (and deletion) of physical

phenomena and changing the form of algorithms a relatively simple matter. We have added

two phenomena by adding the appropriate source terms to the predictive equations. These

are deposition of hydrogen chloride on surfaces and mechanical ventilation. The former has

been added using an analogy with convective heat transfer.

Finally, the chemistry scheme has been changed to reflect more accurately the actual

kinetics processes which take place. This change does not require any changes in external

files, but it is important to understand what is taking place internal to the model, in order to interpret the results properly. In the previous version of the model, cElorine and "cyanide" were treated as minor species and the fuel was assumed to be devoid of oxygen. These

simplifications have been remedied.

2.1 Hydrogen Chloride Deposition

Production of hydrogen chloride from a fire can result in a serious toxicity problem. It has been shown [3] that significant amounts of the substance can be removed by adsorption

by surfaces which contact smoke. In our model, HCl production is treated like any other

species (for details, see the section on chemistry). However, an additional term is required to allow for deposition on, and subsequent absorption into, material surfaces.

The physical configuration that we are modeling is a gas layer, either the upper or lower zone, adjacent to a surface, such as a wall. A gas layer is at some temperature Tg with a concomitant density of hydrogen chloride, p^jQ. The mass transport coefficient is calculated

based on the Reynolds analogy with mass and heat transfer: that is, hydrogen chloride is mass

being moved convectively in the boundary layer, and some of it simply sticks to the wall

surface rather than completing the journey during the convective roll-up associated with eddy

diffusion in the boundary layer. The boundary layer at the wall is then in equilibrium with the

wall. The latter is a statistical process and is determined by evaporation from the wall and

stickiness of the wall for HCl molecules. This latter is greatly influenced by the concentration

of water in the gas, in the boundary layer and on the wall itself.
Source Terms

gas layer

at T and p g HCl

k = transport

^ coefficient

(m/s)

<-

wall boundary layer

at p^blHCl

k = equilibrium

^ coefficient

(m)

<- ->

wall

at T , m , w HCl.w

k = wall

s absorption

coefficient

(1/s) >

Schematic of hydrogen chloride deposition region

The rate of addition of mass of hydrogen chloride to the gas layer is given by

d

dt

mjja = source - k^ x (p„c, -

PbiHci) x K

where source is the production rate from the burning object plus flow from other

compartments. For the wall concentration, the rate of addition is

"77"Ha.w ^ ^c X (Pna ~ PbiHci) ~ *^s ^ TMHa.w

where the concentration in the boundary layer, PbiHci' i^ related to the wall surface

concentration by the equilibrium constant k^,

PblHQ ~ "hCUw / "^e-

(1)

(2)

(3)

We never actually solve for the concentration in the boundary layer, but it is available, as is a boundary layer temperature if it were of interest. The transfer coefficients are

k. - ATxp„xc„

(4)

k. -

bj X e

1500 T„

1500

1 + bjxe

b5x b6

1 + PhjO

Phcl

(p

\b7

HjO^t '^o,%)

(5)

k^ = bj X exp

(6)

The only values currently available [4] for these quantities are
Refinement of a Model for Fire Growth and Smoke Transport

Surface bi b2 b3 b4 bs b6 b7

units -> m m^/kg s-i J/g-mol

*

Painted Gypsum 0.0063 191.8 0.0587 7476. 1.38 1.021 0.431

PMMA 9.6x10-5 0.0137 0.0205 7476. 0.19 1.0 0.431

Ceiling Tile 4.0x10-3 0.0548 0.123 7476. 0.2" 1.0 0.431

Cement Block 1.8x10-2 5.48 0.497 7476. 0.2" 1.0 0.431

Marinite*"" 1.9x10-2 0.137 0.030 7476. 0.2" 1.0 0.431

These "b" coefficients are parameters which are found by filling experimental data to equations (1) through (6). These coefficients reproduce the adsorption and absorption of

HCl very well. The concept has not yet been tested in a wide variety of experiments, nor a wide variey of materials, so the accuracy of the general concept has not yet been determined.

2.2 Chemistry

The essence of the change in the chemistry scheme is to allow for a more realistic fuel

composition, i.e., include oxygen and chlorine as part of the fuel. The key words have not

changed, but one of them has a new meaning. The oxygen parameter, 02, now refers to the

ratio of the mass of oxygen in the fuel to the total fuel mass being pyrolized.

The fuel burning rate in terms of the carbon production is

Am^ = {-} X Am^ (7)

where {—} is the multiplier in the fuel production

(-i-|i*f p C

HCl ^ HCN ^ O

, ^ c c c

(8)

The following definitions are for the heat release rate as a function of the fuel pyrolysis rate,

and the heat release rate based on oxygen consumption. H/C, HCl/C, HCN/C and O/C are the

ratio of that species to carbon in the fuel. The key words [1] associated with these ratios are HCR, HCl, HCN and 02 respectively. The HCl and HCN key words refer to the ratio of that

* Very approximate - insufficient data for high confidence value
Source Terms

species to the fuel, that is HCN/f and HCl/f. The relationship will be discussed later. Note

that the subscript "S" is used to designate soot, and we assume it consists primarily of carbon.

aQ - Anij X hj.

aQ

Afflo = -

1.32x10"'

AniQ(needed) = aiHq - AmQ(in the fuel)

h.

aiHq = Am, X -, and

1.32x10"^

Ain (actual) '-minimum of {Am (available), Am (needed)}

(9)

(10)

(11)

(12)

(13)

Essentially, we limit the amount of fuel that is burned, as opposed to the amount that is pyrolyzed, to the lesser of the amount pyrolyzed and that required to consume the available

oxygen. The Amo(actual) is the quantity used below. (See sect. 3.2 for an additional

discussion whereby this term is calculated.)

We begin with the mass balance equation. The mass consumed as pyrolyzate plus

oxygen must reappear as product. The terms in parenthesis are the ratios of the masses of

the species shown. For example, (HCl/C) is the relative production rate of hydrogen chloride

to fuel carbon pyrolysis.

AHlf /O

Am, + Am„ = Am, + Am^x ' °

' ^

1.32x10^ {-} [C^

= Am^o^ + Am^o + Affig + Am^^o + Am^^^i + ^hcn

(14)

We then substitute the following definitions of mass produced of each species based on the

amount of carbon (ala. fuel) consumed as

AmHa

HCl

Am

C

X Am,

HCl

I f X Am,

HCN

Am,up h7

fHCN^

X Am^, - X Am^

4-\xAm^, = 9 X H

X Am^ - 9 X — X 'cJ {-}

(15)

(16)

(17)
Reflnement of a Model for Fire Growth and Smoke Transport

^^Oj = CO,

I c

X Am, (18)

Am^ = '1X Am^, = CO,

I C )

^ s

^ CO,

X Am^, -

' s

^ VCO.;

X Am,CO,

(19)

Am rco\

CO X Am^ =

i c J X

[CO]

[coj

X Am^, -* CO

CO,2/

X Am^o, (20)

Substituting the above definitions into the mass balance equation yields:

^CO,^

{-}x 1 + he _ O/C ) 1.32x10'' {-}

HCl HCN H^ + —

C)

\ S CO "1 1 + + COj CO2

(21)

With this definition, we can substitute back into the equation for carbon dioxide production,

which yields

1 + AmCO, = Am, X

O/C

1.32x10"^ {-}

I

HCl , HCN ^ r

c c C*^

1 + CO

(22)

CO, CO2; We can now substitute this equation back into equations (19) and (20) to find the soot and

carbon monoxide production. The form in which we cast these equations evolves naturally

from the properties of combustion. Hydrogen, carbon and bound oxygen are properties of the

fuel. They can be measured experimentally independent of the combustion process. Thus we

use these ratios as the basis of the scheme. In a similar sense, hydrogen chloride and

hydrogen cyanide are properties of the pyrolysis process. So hydrogen chlorine and hydrogen

cyanide production are specified with respect to the fuel pyrolysis. Normally this is how they

are measured, for example with the cone calorimeter, so we can use the measured quantities

directly. Other than the cyanide, chloride and water production, hydrogen does not play a

role. In general, hydrogen has much more of an affinity for oxygen than carbon, so almost all of the hydrogen will be utilized. This dictates our next choice, which is that soot is essentially

all carbon. On a mass basis this is certainly true. On a molecular basis, however, it may not

be so simple. Carbon dioxide is a direct product of combustion, and the assumption is that

most carbon will end up here. Carbon monoxide and soot are functions of incomplete

combustion. Thus they depend on the environment in which the burning takes place. They

are in no case a function of the pyrolysis process itself. Thus the production of these

products are specified with respect to the carbon dioxide. At present, we must rely on

measured ratios, but this is beginning to change as we gain a better understanding of the
Source Terms

combustion process. So carbon goes to one of three final species, carbon dioxide, carbon

monoxide or soot, with the particular branching ratio depending on the chemistry active at the

time.

Equations (15) and (16) are used in terms of the carbon production. We now need to

recast HCl and HCN in terms of fuel production rather than carbon production, since that is how they are measured. Since HCl and HCN are similar, we will just make the argument for

one, and then assume that the derivation is the same. One simplification will be possible for

the HCN though, and that is that its production rate is always much less than the pyrolysis

rate.

Since {—} is just f/C,

[ f J

^ H HCl HCN O 1 + — + + + —

c c c c

(23)

Therefore

Hcn j^) c c

1 - HCl

I C I f )

(24)

and for hydrogen cyanide we have

f ilCN \ ^ (^CN\ ^ ^ ^ H ^ HCl ^ O (25)

In these latter cases, we assume that the cyanide ratio (HCN/C) is small compared to unity. It

is the HCl/C and HCN/C ratios which are used by the model.

In summary, we can predict the formation of products of combustion, carbon dioxide,

carbon monoxide, soot, water, cyanide, and hydrogen chloride given the branching ratios

CO/CO2, S(soot)/C02 and the composition of the fuel, H/C, O/C, HCl/f and HCN/f.

2.3 Mechanical Ventilation

The model for mechanical ventilation is based on the theory of networks. This is a simplified

form of Kirchoff's law which says that flow into a node must be balanced by flow out of the

node. There is a close analog to electrical networks for which the flow consists of electrons. In the case of ventilation, the flow is formed by molecules of air. The conservation equation

differs slightly from that of an electrical system, but the basic ideas carry over. The former

case, we have
Refinement of a Model for Fire Growth and Smoke Transport

voltage = current x resistance.

In the present case we have

pressure change = mass flow x mass flow x resistance.

So the application of network theory is used, although the circuit laws are slightly different. In

practice, as with the electrical analog, one solves the problem by summing all of the equations

for the nodes, and require that the mass be conserved at each node. Thus we turn the

equation around and put it into the form

mass flow = conductance x (pressure drop across a resistance)''^'.

For each node, this flow must sum to zero. There are several assumptions which are made in computing this flow in ducts, fans, elbow, etc. First, we assume unidirectional flow. Given the

size of ducts, and the nominal presence of fans, this is quite reasonable. Second, in the

conservation law for energy, there is a work term which describes compression or expansion of

a volume. There is no such analogous term in the solution of the mass flow equations for

ventilation. This is reasonable so long as a ventilation system is not being used to increase or

decrease the pressure within a structure. It is still acceptable for connecting systems at different pressures. Further, the effect that a change in pressure within a duct has on the

flow characteristics is likewise ignored. Once again, for most of the cases of interest this is a reasonable assumption. Finally, the particular implementation used here [5] does not allow

for reverse flow in the duct system. The difficulty lies in describing how a fan behaves in such

a case.

Given that we can describe mass flow in terms of pressure differences and

conductance, the conservation equation for each node is

E'^ij^O- (26)

J The index "j" is a summation over connections to a node, and there is an equation "i" for each

node. The remaining problem is to specify the boundary conditions. At each connection to a compartment, the pressure is specified. Then, given that How is unidirectional, the mass and

enthalpy flow into or out of a room can be calculated explicitly. Thus we end up with a set of

equations of the form

10
Source Terms

fi(Pi,P2, ...) =

fj(P,J»2, ...) =

(27)

f„(P„P3, ...) = 0.

This is an algebraic set of equations that is solved simultaneously with the equations for flow

in the compartments.

The equations describe the relationship between the pressure drop across a duct, the

resistance of a duct, and the mass flow. The pressure can be changed by conditions in a compartment, or a fan in line in the duct system. Resistance arises from the finite size of

ducts, roughness on surfaces, bends and joints. To carry the electrical analog a little further,

fans act like constant voltage sources. The analogy breaks down, however, in that the voltage,

current and resistance are related by the square of the current, rather than being linearly

proportional. Since we are using the current form of the conservation equation to balance

the system, recast the flow in terms of a conductance

rii = G X /IF.

The conductance can be expressed generally as

G = 2 p

V ^0

;

(28)

(29)

where Cq is the flow coefficient (usually a loss term), and Aq is the area of the inlet, outlet,

duct, contraction or expansion joint, coil, damper, bend, filter, and so on. Their values for the

most common of these items are tabulated in the ASHRAE Handbook [6].

Ducts are long pipes through which gases can flow. They have been studied much

more extensively than other types of connections. For this reason, eq (30) can be put into a form which allows one to characterize the conductance in more detail, depending on the type

of duct, such as oval, round, square, and so on. The form derives from the Darcy equation and

is

G = F L

1/2

2 p D^ V

where F is the friction factor and can be calculated from

(30)

11
Refinement of a Model for Fire Growth and Smoke Transport

3.7 D.

2.51 ^ (31)

For each node in the system, one has an entry of the form of eq (29). This set of

equations is then solved at each time step. In the present form, the solution to the duct

system is split from that of the buoyancy driven flow. This is justified based on the long time

constant for change of the flow pattern in such a system. Implicit in this assumption is that

there is only a very weak interaction between the systems of equations. When we begin to deal with the problem of flow reversal then the fan characteristics will be coupled much more

closely with the buoyancy driven flow and we will have to reformulate the solution.

12
Source Modules

3. SOURCE MODULES

The routines described below come directly from the FAST program. The modules

have been annotated to make them more understandable. For example, comments within the

code which are directives for changing the routines are not included. There are also

comments which appear here which are not shown in the actual code. The part that is strictly in upper case is FORTRAN code, whereas text in lower or mixed case are extra comments.

3.1 Hydrogen Chloride Deposition

SUBROUTINE HCITRAN (LAYER, COMP, ARW, TG , TW, HWDOT, NWW)

FAST COMMON BLOCK GOES HERE

C LAYER IS UPPER OR LOWER

C COMP IS THE COMPARTMENT NUMBER (1 to nr)

C ARW IS THE AREA OF THE WALL (DSOURC ACEILI , AUPPER, ALOWER, AFLOOR)

C TG IS THE RELEVANT GAS TEMPERATURE

C TW IS THE CORRESPONDING WALL TEMPERATURE

C HWDOT IS THE WALL CONCENTRATION DERIVATIVE

C THE GAS LAYER DERIVATIVE IS CALCULATED GLOBALLY AS NETMAS

C NWW IS THE WALL NUMBER 1=>CEILING , . .

.

C HCIG IS THE GAS PHASE DENSITY (KG/M"3)

C HCIW IS THE WALL DENSITY (KG/M"2)

C RK IS THE CONSTANT "kc" WHICH IS THE DEPOSITION COEFFICIENT (M/S)

C RKE IS THE EQUILIBRIUM COEFFIENT BETWEEN THE GAS AND SOLID (WALL)

C H20S IS SATURATION CONCENTRATION, AND H20 CURRENT CONCENTRATION

INTEGER COMP

C

the following section sets the environment variables

IF (LAYER. EQ. UPPER) THEN

CVOL = P(C0MP+N2)

ELSE

CVOL = MAX(VR(COMP)-P(COMP+N2),PMIN(COMP+N2))

ENDIF

HCIG = MASS (LAYER, COMP, 6) / CVOL

HCIF = HCIG * TG * 2.25E-3

HCIP = HCIF * 1.0E6

HCIW = HWJ (NWW, COMP)

RHO = (RAMB(COMP)*TAMB(COMP))/(PAMB(COMP)+POFSET)

* (P(COMP)+POFSET)/TG

FLUX = QSCNV (NWW, COMP)

H20 = MASS (LAYER, COMP, 8) / CVOL

TWC = TW - 273.15

13
Reflnement of a Model for Fire Growth and Smoke Transport

the transfer coefficients are kept in the thermophysical data base, and are read in by NPUTT

Bl = HC1BF(1,NWW,C0MP)

B2 = HC1BF(2,NWW,C0MP)

B3 = HC1BF(3,NWW,C0MP)

B4 = HC1BF(4,NWW,C0MP)

B5 = HC1BF(5,NWW,C0MP)

B6 = HC1BF(6,NWW,C0MP)

B7 = HC1BF(7,NWW,C0MP)

if properties are not specified, then we assume no deposition

IF (Bl.LE.O) THEN

HWDOT =0.0

RETURN

ENDIF

calculate HCl gas-surface partition coefficient, where H2O is the saturation pressure of water

and bcoef is the convective transfer coefficient

TWC2 = TWC * TWC

TWC3 = TWC2 * TWC

HC1F2 = HCIF * HCIF

HC1F3 = HC1F2 * HCIF

IF (TWC .LE. 40.) THEN

IF (HCIP .GT. 10.) THEN

H20S = (1.8204 - 0.18890*LOG(HC1P)

+ 0.06466*TWC + 1 . 650E-3*TWC2 + 7 . 408E-5*TWC3) / TW

ELSE

EXPTW = EXP(17. 64262-5164. 1/TW)

BCOEF = (7.696E-5 + 3 . 5920E-6*TWC

-I- 9.166E-8*TWC2+4.116E-9*TWC3)

/ TW-1.E-7*EXPTW

H20S = 0.018*EXPTW + 1 . 8E4*BC0EF*HC1P

ENDIF

ELSEIF ( (TWC. GT. 40.0) .AND. (TWC. LE. 60.0)) THEN

HC1F4 = HC1F2 * HC1F2

HC1F5 = HC1F4 * HCIF

H20S = (7.044 - 2.2416E3*HC1F - 3 . 874E-3''tTWC2 + 2 . 328E-4*TWC3

+ 2.376E6*HC1F2 - 5 . 527E8-'tHClF3 + 4 . 918E10^-HC1F4

- 1.359E12*HC1F5 - 1 .4033E2*TWC*HC1F + 2 . 431E4*TWC*HC1F2

- 1.6023E6*TWC*HC1F3) / TW

ELSEIF ( (TWC. GT. 60.0) .AND. (TWC. LE. 80.0)) THEN

HC1F4 = HC1F2 * HC1F2

HC1F5 = HC1F4 * HCIF

H20S = (107.46 - 4.129*TWC + 5 . 096E-2-A-TWC2 - 3 . 1915E8*HC1F3

+ 1.0408E10*HC1F4 - 2 . 2793E11*HC1F5 - 5 . 8194*TWC2*HC1F

+ 7.6883E4*TWC*HC1F2 - 7 .4363E2'VTWC2*HC1F2 + .059067*TWC3*HC1F + 1 . 8132E6^'TWC-A'HC1F3) / TW

ELSEIF ( (TWC. GT. 80.0) .AND. (TWC. LE. 95.0)) THEN

HC1F4 = HC1F2 * HC1F2

HC1F5 = HC1F4 * HCIF

H20S = (2.583E2 - 8.0386-"TWC + 1 . 739E5---HC1F + 7 . 608E-2*TWC2

- 1.5492E7*HC1F2 + 3 . 956E9-A'HC1F3 - 2 . 065E11*HC1F4

+ 1.3747E13*HC1F5 - 4 . 086E3*TWC^'HC1F + 24 . 06""TWC2>5rHClF + 1.3558E5*TWC*HC1F2 - 3 . 076E7*TWC*HC1F3) / TW

ELSEIF ( (TWC. GT. 95.0). AND. (TWC. LE. 110.0)) THEN

14
Source Modules

H20S = (6.431E2 - 16.374*TWC + 2.822E5*HC1F + 0.12117*TWC2

- 8.224E7*HC1F2 - 7 . 387E6*HC1F3 - 5 . 247E3*TWC*HC1F

+ 24.30*TWC2*HC1F + 1 . 5465E6*TWC->HC1F2

- 7.250E3*TWC2*HC1F2) / TW

ELSEIF (TWC.GT. 110.0) THEN

H2OS=0.2885*EXP(18.3036-3816.44/(TW-46.13))/TW

ELSE

STOP 'Error in hcltran - h2o out of range'

END IF

C CALCULATE THE COEFFICIENTS, FIRST THE CONVECTIVE COEFFICIENT RK, THEN

C THE MASS TRANSFER (EQUILIBRIUM) COEFFICIENT, RKE

IF (TW .GE. TG) THEN

RK = 8.33E-3

ELSE

RK = ABS(FLUX/(MAX(0.001,TG-TW)*RHO*CP))

ENDIF

IF (H20S.GT.H20) THEN

EXPTW = EXP(1500/TW)

RKE = Bl * EXPTW/ (1.+B2*EXPTW*HC1G)

* (l.+B5*H20**B6/((H20S-H20)**B7))

ELSE

RKE = 1.0E4

ENDIF

C CALCULATE THE DERIVATIVES

HCICOF = RK * (HCIG - HC1W/(RKE+1 . E-20)

)

NETMAS(LAYER,C0MP,6) = NETMAS(LAYER, COMP , 6) - HCICOF * ARW

HWDOT = HCICOF - B3 * EXP( -B4/(8 . 31*TW) ) * HCIW

RETURN

END

3.2 Chemistry

CHEMIE is the routine which calculates the heat release rate and species production as described in section 2.2. It has been changed by incorporating the above formulae. The

primary input is the mass pyrolysis rate, and the primary output is the heat generation rate. This routine is only used for a type 2 (constrained) fire.

SUBROUTINE CHEMIE (QPYROL, PYROL, ENTRAIN, NETFUEL, TARGET, LAYER,

. HCRATT, OCRATT, CC02T, C0C02T, CLFRAT, CNFRAT)

"pyrol" is the mass pyrolysis rate from the PYROL routine, and qpyrol the heat generation

rate, "entrain" is the entrainment rate (we are dealing with diffusion limited combustion) and

"netfuel" is the fuel actually burned as opposed to the possible "pyrol" value, "netxx" then are the species production rates, based on the formulae discussed in section 4.5.

15
Reflnement of a Model for Fire Growth and Smoke Transport

FAST COMMON BLOCK GOES HERE

REAL NETFUEL, NEWNET, NETH20, NETC02 , NETCO , NETC , NET02 , NETCL,

NETCN TMASS NETFUL XMASS(NS)

EQUIVALENCE (NET02 ,XMASS(2) ) , (NETC02 ,XMASS (3) ) , (NETC0,XMASS(4) )

,

. (NETFUL,XMASS(7)) , (NETH20,XMASS(8) ) , (NETC ,XMASS(9) )

,

. (NETCN,XMASS(5)) , (NETCL,XMASS(6))

INTEGER SOURCE, TARGET

DATA XMASS/NS*0.0/, 02F/1 . 32E+7/, 02FI/7 . 578E-8/

"source" specifies the compartment of origin of the flow, and "layer" is the corresponding layer

from which the fuel and oxygen originate.

SOURCE = TARGET

TMASS =0.0

DO 2 LSP =1,9

2 TMASS = TMASS + MASS (LAYER, SOURCE , LSP)

TMASS = MAX (TMASS, MINMAS)

02FRAC = MASS(LAYER, SOURCE, 2) / TMASS

* 02ENTR = ENTRAIN * 02FRAC

* ALPHA =1. / ( 0.207 - MIN(0 . 20 , LIM02)

)

* 02INDEX = MAX(0. , (02FRAC-LIM02)'!--ALPHA) * 02MASS = 02ENTR * (1 . 0-EXP( -10 . 0^-02INDEX)

)

OOSTOK = 13200000. / HCOMBA

QPYROL = MAX(0. ,MIN(PYROL, 00ST0K*02MASS) ) * HCOMBA

NETFUEL = QPYROL / HCOMBA

C THIS IS THE REAL KINETICS SCHEME AS DRIVEN BY DIFFUSION

C FIRST CONVERT CHLORINE AND CYANIDE PRODUCTION TO CARON BASED RATIOS

CLCRAT = CLFRAT * (1 . 0+HCRATT+OCRATT)/(1 . 0-MIN(0 . 99999 , CLFRAT)

)

CNCRAT = CNFRAT * (1 . O+HCRATT+OCRATT)

FCRATT = (1.0 + OCRATT + HCRATT + CLCRAT + CNCRAT)

NETFUL = - NETFUEL

NET02 = - QPYROL * 02FI

C NOW DO THE "KINETICS SCHEME"

NETH20 = 9.0 * NETFUEL * HCRATT / FCRATT

FACTORl = 1.0 + HC0MBA*02FI - OCRATT / FCRATT

FACT0R2 = (CLCRAT + CNCRAT + HCRATT) / FCRATT

NETC02 = (FACTORl - FACT0R2) ^' NETFUEL / (1 .+COC02T+CC02T)

NETCO = NETC02 * C0C02T

NETC = NETC02 * CC02T

NETCL = CLFRAT * NETFUEL

NETCN = CNFRAT * NETFUEL

1 NETMAS (UPPER, TARGET, I) = NETMAS (UPPER, TARGET, I) + XMASS(I)

C NO POINT IN ENTRAINING FROM THE UPPER LAYER INTO THE UPPER LAYER

IF (LAYER. EQ. UPPER) RETURN

C ADD IN THE FLOW ENTRAINED BY THE PLUME

DO 8 LSP = 1, NS

16
Source Modules

IF (.NOT.ACTIVS(LSP)) GO TO 8 PLUME CONTRIBUTION FOR ALL ENTRAINED GASES

NEWNET = ENTRAIN * MASS (LOWER, SOURCE , LSP) / OLDMAS (LOWER, SOURCE)

NETMAS (UPPER, TARGET, LSP) = NETMAS (UPPER, TARGET, LSP) + NEWNET

NETMAS( LOWER, TARGET, LSP) = NETMAS (LOWER, TARGET, LSP) - NEWNET

8 CONTINUE

RETURN

END

Figure 1. Fraction, (L0-EXP(-10.0*O2INDEX)), as a function of oxygen and its limiting index.

The lines in the routine CHEMIE marked with an asterisk form the basis of the limit on the actual burning rate alluded to in section 2.2. The fourth line, for 02MASS, is a function of the limiting oxygen index and the percent of oxygen present in the environment.

Figure 1 shows the fraction (1.0-EXP(-10.0*O2INDEX)). The oxygen concentration varies

from 0% to 21%. The limiting oxygen index varies from 0% to 17%. Any cross section of

this graph will be just like the curve discussed in the Technical Reference Guide [1]. Noteworthy, however, is the fact that as the two rates approach the high limit (21%), the curve steepens. This is an artifact of the approximation to the cutoff, and is not necessarily

reflected in the reality of the chemistry being approximated.

17
Refinement of a Model for Fire Growth and Smoke Transport

33 Mechanical Ventilation

This is the internal part of the routine HVAC. It is the section that is called

by the solver.

C GET STUFF FROM THE OUTSIDE WORLD

CALL HVFREX

C DO THE MECHANICAL VENTILATION

CALL HVMFLO

CALL HVSFLO

C TELL THE WORLD WHAT HAS HAPPENED

CALL HVTOEX

RETURN

END

SUBROUTINE HVFREX

This routine retrieves data from the compartments and sets it up for the

mechanical ventilation.

FAST COMMON BLOCKS GO HERE

DO 10 II = 1, NEXT

I = HVN0DE(1,II)

J = HVN0DE(2,II)

Z = ZZHIAY(I,LOWER)

IF (HVELXT(II) .LT.Z) THEN

lAYER = LOWER

ELSE

LAYER = UPPER

END IF

ZL = MIN(Z, HVELXT(II))

XXO = O.ODO

ZU = MIN(XXO, HVELXT(II)-ZL)

RU = ZZRHO(I,UPPER)

RL = ZZRHO(I,LOWER)

HVP(J) = ZZRELP(I) - (RU*ZU + RL*ZL)--=^HVGRAV

IF (LAYER. EQ. LOWER) THEN

HVEXTT(II) = ZZTEMP(I,LOWER)

VLAYER = ZZVOL(I,LOWER)

ELSE

HVEXTT(II) = ZZTEMP(I,UPPER)

VLAYER = ZZVOL(I,UPPER)

ENDIF

DO 11 LSP = 1, NS

IF (ACTIVS(LSP)) HVEXCN(II,LSP) = MASS (LAYER, I , LSP) / VLAYER

11 CONTINUE

10 CONTINUE

18
Source Modules

RETURN

END

SUBROUTINE HVTOEX

Assign results of hvac simulation to the transfer variables (hvextt, hvexcn).

FAST COMMON BLOCKS GO HERE

DO 10 II = 1, NEXT

I = HVN0DE(1,II)

J = HVN0DE(2,II)

IB = ICMV(J,1)

Z = ZZHLAY(I,LOWER)

IF (HVELXT(II) .LT.Z) THEN

LAYER = LOWER

LLAYER = UPPER

ELSE

LAYER = UPPER

LLAYER = LOWER

ENDIF

HVEFLO (LAYER, II) = HVFL0W(J,1)

HVEFLO (LLAYER, II) = 0. ODD

IF (HVFL0W(J,1) .GT. O.ODO) THEN

HVEXTT(II) = TBR(IB)

DO 11 K = 1, NS

IF (ACTIVS(K)) HVEXCN(II,K) = HVCONC(IB,K)

11 CONTINUE

ENDIF

10 CONTINUE

RETURN

END

SUBROUTINE HVMFLO

Routine to calculate the mass flow thru a generic duct. The ducts have

been "sanitized" by using coefficients from the ASHRAE handbook on ventilation, so all ducts,... look the same regardless of what the user

thinks he is doing.

FAST COMMON BLOCK GOES HERE

LOGICAL CONV

INTEGER OUTITR, INITR, ITMAX

ITMAX=50

EPS=l.E-5

C CALCULATE AVERAGE TEMPERATURES AND DENSITIES FOR EACH BRANCH

DO 9 IB = 1, NBR

PAV = (HVP(NA(IB))+HVP(NE(IB)))/2. + POFSET

ROHB(IB) = PAV/(HVRGAS*TBR(IB))

9 CONTINUE

C START THE ITERATION CYCLE - ACTUALLY A PRETTY SIMPLE ITERATION SCHEME

19
Reflnement of a Model for Fire Growth and Smoke Transport

OUTITR =

1 INITR =

the first section calculates the resistivity due to various parts of

the system - this assumes an electrical analog for flow in a network

C INITIALIZE CONDUCTANCE - THIS IS THE ELECTRICAL ANALOG

DO 11 IB = 1, NBR

11 CE(IB)=0.

C CALCULATE CONTRIBUTION DUE TO DUCTS

DO 10 ID = 1, NDT

IB = IBRD(ID)

VEL = BFLO(IB)/(ROHB(IB)*DA(ID))

RE = VEL*DE(ID)/HWIS(TBR(IB))

F = HVFRIC(RE,RR(ID))

CDUCT=F*DL(ID)/(2.*ROHB(IB)^-DE(ID)*(DA(ID)*^-2))

10 CE(IB)=CE(IB)+CDUCT

C CALCULATE CONTRIBUTION DUE TO SIMPLE FITTINGS

DO 20 IFT = 1, NFT

IB=IBRF(IFT)

CFIT=CO(IFT)/(2.*ROHB(IB)*(AO(IFT))**2)

20 CE(IB)=CE(IB)+CFIT

C CONVERT FROM PRESSURE TO MASS FLOW RATE COEFFICIENTS

DO 40 IB = 1, NBR

IF (CE(IB) .NE.O.O) THEN

CE (IB) = SIGN(1./SQRT(ABS(CE(IB))) , CE(IB))

ENDIF

40 CONTINUE

C CALCULATE HYDROSTATIC PRESSURE DIFFERENCE TERMS

DO 70 I=1,NN0DE

DO 70 J=1,NCN0DE(I)

70 DPZ(I,J)=ROHB(ICMV(I,J))*HVGRAV*(HVGHT(IN(I,J))-HVGHT(I))

C SOLUTION OF MASS FLOW EQUATIONS

This is the iteration section - go until the mass flow and pressure drop balance.

The inner iteration is for pressure drop with a given flow, whereas the outer iteration is for

changing mass flow (velocity), and the effect is then reflected back in the friction,...

5 CONV=.TRUE.

DO 30 I=1,NN0DE

IF(NCNODE(I) .GT. 1) THEN

DF=0.

F=0.

DO 25 J=1,NCN0DE(I)

20
Source Modules

DP=HVP(IN(I,J))-HVP(I)+DPZ(I,J)

IF(NF(ICMV(I,J)) .EQ. 0) THEN

RESISTIVE BRANCH CONNECTION

ROOT=SQRT(ABS(DP))

F = F + SIGN(CE(ICMV(I,J))~A-ROOT, DP)

ROOT = MAX(1.E-9,R00T)

DF=DF-CE(ICMV(I , J) )/(2 .*ROOT)

ELSE

FAN BRANCH CONNECTION

K=NF(ICMV(I,J))

IF(NE(ICMV(I,J)) .NE. I)THEN

flow is at fan inlet

F=F-HVFAN(I,J,K,DP,DFF)

DF=DF+DFF

ELSE

flow is at fan exit

DP=-DP

F=F+HVFAN(I,J,K,DP,DFF)

DF=DF+DFF

ENDIF

ENDIF

25 CONTINUE

HVP(I)=HVP(I)-F/DF

IF(ABS(F) .GT. EPS )CONV=. FALSE.

ENDIF

30 CONTINUE

INITR = INITR + 1

IF ( INITR. GT.ITMAX) STOP 'HVMFLO excessive inner iterations'

IF (.NOT. CONV)GO TO 5

C END OF SOLUTION OF MASS FLOW EQUATIONS NOW CALCULATE MASS FLOWS

this is the outer iteration

DO 60 I=1,NN0DE

F = 0.0

DO 50 J=1,NCN0DE(I)

DP=HVP(IN(I,J))-HVP(I)+DPZ(I,J)

IF(NF(ICMV(I,J)) .EQ. 0) THEN

ROOT = SQRT(ABS(DP))

HVFLOW(I,J) = SIGN(CE(ICMV(I,J))*ROOT, DP)

BFLO(ICMV(I,J)) = ABS(HVFLOW(I,J))

F = F + HVFLOW(I,J)

ELSE

C FAN BRANCH CONNECTION

K=NF(ICMV(I,J))

IF(NE(ICMV(I,J)) .NE. I)THEN

21
Reflnement of a Model for Fire Growth and Smoke Transport

HVFLOW(I,J)=-HVFAN(I,J,K,DP,DFF)

F=F+HVFLOW(I,J)

ELSE

DP=-DP

HVFLOW(I,J)=HVFAN(I,J,K,DP,DFF)

F=F+HVFLOW(I,J)

ENDIF

ENDIF

50 CONTINUE

60 CONTINUE

OUTITR = OUTITR + 1

IF (OUTITR. GT. 20) STOP 'HVMFLO failed to converge'

IF (INITR,GT.3) GO TO 1 RETURN

END

SUBROUTINE HVSFLO

C ROUTINE TO CALCULATE SMOKE & HEAT FLOWS

FAST COMMON BLOCK GOES HERE

REAL HVCA(NS) , HVTA

C CALCULATE TEMPERATURE & SMOKE FLOW AT THE CONNECTING NODES

C WE ASSUME THAT THE PRESSURE AND TOTAL MASS FLOW EQUATIONS

C HAVE BEEN SOLVED

DO 30 I = 1, NNODE

HVTA=0

.

FLOWIN=0

.

DO 19 K = 1, NS

19 HVCA(K) =0.0

DO 20 J = 1, NCNODE(I)

IF (HVFLOW(I,J) .GT.0.0) THEN

FLOWIN = FLOWIN + HVFLOW(I,J)

IB = ICMV(I,J)

HVTEMP = HVFLOW(I,J)

HVTA = HVTA + HVTEMP*TBR(IB)

DO 23 K = 1, NS

IF (ACTIVS(K)) HVCA(K) = HVCA(K) + HVTEMP*HVCONC(IB ,K)

23 CONTINUE

ENDIF

20 CONTINUE

IF ( FLOWIN. GT. 0.0) THEN

HVTA = HVTA / FLOWIN

DO 24 K = 1, NS

IF (ACTIVS(K)) HVCA(K) = HVCA(K) / FLOWIN

24 CONTINUE

ELSE

DO 21 II = 1, NEXT

IF (HVN0DE(2,II).EQ.I) THEN

HVTA = HVEXTT(II)

DO 25 K = 1, NS

IF (ACTIVS(K)) HVCA(K) = HVEXCN(II,K)

25 CONTINUE

GO TO 22

22
Source Modules

END IF

21 CONTINUE

STOP 'MECH VENT. MODULE - YOU CAN NOT GET HERE FROM THERE'

22 CONTINUE

END IF

calculate the temperature and concentrations in the ducts and fan cages

DO 40 J = 1, NCNODE(I)

IB = ICMV (I, J)

IF (HVFLOW(I,J) .LT.0.0) THEN

IF (NF(IB) .EQ.O) THEN

FACTOR - -MIN(1. ,HVFLOW(I,J)*HVDELT/(HVDVOL(IB)*ROHB(IB)))

TBR(IB) = TBR(IB)*(1. -FACTOR) + HVTA*FACTOR , DO 42 K = 1, NS

IF (ACTIVS(K)) HVCONC(IB,K) = HVC0NC(IB,K)*(1 . -FACTOR)

+ HVCA(K)*FACTOR

42 CONTINUE

ELSE

TBR(IB) = HVTA

DO 41 K = 1, NS

IF (ACTIVS(K)) HVCONC(IB,K) = HVCA(K)

41 CONTINUE

ENDIF

ENDIF

40 CONTINUE

30 CONTINUE

RETURN

END

FUNCTION HVFRIC(RE,RR)

C CALCULATES FRICTION FACTOR FROM THE COLEBROOK EQUATION

IF(RE .GT. 2300)GO TO 1

HVFRIC=64./RE

RETURN

1 X=2.4*RE**0.0925

1=0

2 C=RR/3.7+2.51*X/RE

1=1+1

G=X+2.*AL0G 10(C)

DG=1+2.18016/(RE*C)

XN=X-G/DG

IF(I .GT. 10)STOP

IF(ABS(XN-X) .LT. .003)00 TO 5 X=XN

GO TO 2

5 HVFRIC=1/XN**2

RETURN

END

FUNCTION HVFAN(II,JJ,K,DP,DFF)

C

C THIS FUNCTION RETURNS THE MASS FLOW RATE THROUGH A FAN

C

23
Reflnement of a Model for Fire Growth and Smoke Transport

C K = FAN ^fUMBER

C DP = HEAD PRESSURE ACROSS THE FAN

C DFF= DERIVATIVE OF FAN FLOW (CALCULATED & RETURNED)

C

FAST COMMON BLOCKS GO HERE

LOGICAL ERRORL, ERRORH

DATA ERRORL, ERRORH/ 2*. TRUE./

C

ROH=ROHB ( ICMV ( I I , JJ )

)

IF (DP.LT.HMIN(K)) THEN

IF (ERRORL) THEN

WRITE (lOFILO, 700) DP

ERRORL = .FALSE.

ENDIF

HVFAN = QMIN(K)

DFF = DFMIN(K)*ROH

ELSE IF(DP.GT.HMAX(K)) THEN

IF (ERRORH) THEN

WRITE (lOFILO, 700) DP

ERRORH = .FALSE.

ENDIF

HVFAN = QMAX(K)

DFF - DFMAX(K)*ROH

ELSE

F=HVBC0(K,1)

DF=0 . ODD

XX=1 . ODD

DO 1 J = 2, NFC(K)

DF = DF + FL0AT(J-1)---HVBC0(K,J)*XX

XX = XX*DP

F = F + HVBCO(K,J)*XX

1 CONTINUE

HVFAN = F*ROH

DFF = DF*ROH

ENDIF

RETURN

700 FORMAT(/2X,10('*') , ' Flow outside fan curve, DP = ',1PG12.3)

END

FUNCTION HWIS(T)

INCLUDE 'PRECIS. INC

C

C FUNCTION CALCULATES ABSOLUTE VISCOSITY (PASCAL SECOND)

C BY INTERPOLATION FOR 200 TO 2000 DEG K.

C DATA FROM NASA TECH NOTE D-7488 BY POFERL, D. J. AND

C SVEHLA, R. ,1974 EXCEPT FOR THE VALUE AT 200 DEG K

C WHICH IS FROM THE CRC HANDBOOK OF CHEMISTR & PHYSICS,

C 66TH ED., 1985 PAGE F-42.

C

C T=ABSOLUTE TEMPERATURE IN DEGREES KELVIN

C

LOGICAL ERROR

DIMENSION V(19)

DATA V/13. 1,18. 4, 22. 7, 26. 5, 29. 9, 33. 1,36. 2, 39.1, 41.

+,44.5,47.0,49.4,51.7,54.0,56.3,58.5,60.7,62.9,65.1/

24
Source Modules

DATA ERROR/ . TRUE .

/

I=T/100.D0 - l.DO

IF(I .GE. 19)G0 TO 1

IF (I.LT.l) THEN

IF (ERROR) THEN

WRITE(*,2) T

FORMAT (' OUT OF VISCOSITY INTERPOLATION RANGE = ',F10.3)

ERROR = .FALSE.

ENDIF

1 = 1

ENDIF

Tl = 100.DO*(1.DO+FLOAT(I))

IM = I + 1

HWIS = (V(I) + (V(IM) - V(I))*(T - Tl)*0.0lD0)*1.0D-6

RETURN

HWIS=V(19)*lD-6

RETURN

END

25
Refinement of a Model for Fire Growth and Smoke Transport

4. DESCRIPTION OF THE DATA FILE USED BY FAST

There are several new key words which are used to describe the mechanical ventilation. They

are given here in the style of chapter 6 of reference [1]. The key words which apply to mechanical ventilation are MVOPN - describe an opening between a compartment and the ventilation system

MVDCT - describe a piece of (circular) duct work

MVFAN - give the pressure - flow relationship for a fan

INELV - specify interior node elevations

An additional key word for diagnostic use CNVG - specify convergence tolerances

and a fuel parameter is

02.

Label

MVOPN

MVDCT

Parameter

(5)

Compartment

Number

Duct Work

Node Number

Orientation

Height

Area

(9)

Node Number

Comments

Connect a compartment to a node in the

mechanical ventilation system.

Specify the compartment number.

Corresponding node in the mechanical ventilation

system to which the compartment is to be

connected.

V for vertical or H for horizontal.

Height of the duct opening above the floor of

the compartment.

Area of the opening into the compartment.

Specify a piece of duct work.

First node number. This is a node in the

mechanical ventilation scheme, not a compartment number (see MVOPN).

26
Description of the Data File Used by FAST

MVFAN

Node Number

Length

Diameter

Absolute

Roughness

Flow

Coefficient

Area

Flow

Coefficient

Area

(9)

First

Node

Second

Node

Minimum

Pressure

Maximum

Pressure

Coefficients

Second node number.

Length of the duct.

All duct work is assumed to be circular. Other

shapes must be approximated by changing the

flow coefficient. This is done implicitly by

network models of mechanical ventilation and

forced flow, but must be done explicitly here.

Roughness of the duct.

Flow coefficient to allow for an expansion or

contraction at the end of the duct which is connected to node number one. To use a

straight through connection (no expansion or

contraction) set to zero.

Area of the expanded joint.

Coefficient for second node.

Area at the second node.

Specify fan curve with power law coefficients.

There must be at least one coefficient.

First node in the mechanical ventilation system to which the fan is connected.

Second node to which the fan is connected.

Lowest pressure of the fan curve. Below this value, the flow is assumed to be constant.

Highest pressure at which the fan will operate.

Above this point, the flow is assumed to stop.

At least one, and a maximum of five coefficients to specify the flow as a function of pressure. See

comments at the end of this section for more

information.

m

m

m

m

m

Pa

Pa

27
Reflnement of a Model for Fire Growth and Smoke Transport

INELV

02

(2xn)

Production

Rate

of the Fuel

Specify interior elevations of the mechanical (#,m)

ventilation nodes. All nodes can be specified, but

the exterior nodes, that is those connected to a compartment, will be set to the compartment

elevation. The heights are absolute heights

above the reference datum specified by TAMB.

The heights are specified in pairs, the node

number followed by the height.

The mass ratio of oxygen to carbon as it becomes kg/kg

available from the fuel.

CNVG (3) Diagnostic parameters

Approximate This is a logical switch. If set to zero, the usual

Conduction heat transfer thru partitions is calculated. If set to any non zero value then the semi-infinite slab

approximation is used.

Convergence Modifies the convergence criterion used by the

Factor solver for the relative error at each time step.

1.0

Pressure

Damping

Used to damp pressure fluctuations. 1.0

The diagnostic parameters must be used with extreme caution. These parameters can not be

set in the data editor for the main model. While running computations within the data editor,

the speed enhancement for the conduction can be utilized. Normally, a linear parabolic

equation is solved for the heat transfer through each partition. The solution is via a successive over-relaxation technique. When the walls are thick, or the simulation time will be

very short, it is reasonable to assume that the thermal wave will not reach the outside

boundary. In this case, there is an analytic solution to the conduction equation which can be

written in terms of the "error function," ERFC [7J. The other two parameters modify the

convergence criteria used by the numerical solver. The default values are unity, and should

normally be left at those values.

Example 1

:

MVDCT 1 3 20. .15 .19E-3 3.30

MVDCT 3 4 44. .2 .19E-3 0.0

MVFAN 4 5 0.0 140. 0.140 3 MVOPN 1 1 H 0. 1.

MVOPN 4 9 V 0. 2.5

INELV 3 40 50 7080

.01767

0.0

,170E-04

0.

0.

-1

0.

0.

803E-05 1.898E-07 -8.104E-10

28
Description of the Data File Used by FAST

Example 2:

MVDCT 1 3 20. .15 .19E-3 3.30 .01767 0. 0.

MVDCT 2 3 20. .15 .19E-3 2.94 .01767 0. 0.

MVDCT 3 4 44. .2 .19E-3 0.0 0.0 0. 0.

MVDCT 5 6 40. .2 .19E-3 .51 .03142 0. 0.

MVDCT 7 4 40. .2 .19E-3 .51 .03142 0. 0.

MVDCT 9 8 40. .2 .19E-3 .51 .03142 0. 0.

MVFAN 4 5 0.0 140. 0.140 3. 170E-04 - 1.803E-05 1.898E-07 -8.104E-10

MVFAN 8 7 0.0 140. 0.140 3. 170E-04 - 1.803E-05 1.898E-07 -8.104E-10

MVOPN 1 1 H 0. 1.

MVOPN 2 2 H 0. 1.5

MVOPN 3 6 H 0. 2.5

MVOPN 4 9 H 0. 2.5

INELV 3 4 5 7 8

This example describes a network which is shown in figure 2.

Compartment Compartment

Node Node

4 /5

Fan#1

Node

6

Node

7

c

Q.O

>

E

Flow

Fan #2

Figure 2. Node arrangement for example 2.

The fan coefficients are simple the coefficients of an interpolating polynomial for the

flow speed as a function of the pressure accross the fan housing. The fan described in the

29
Reflnement of a Model for Fire Growth and Smoke Transport

previous example was for a pressure range of zero to 140 Pascals. An example of such a

calculation is the following:

The following data (flow in kilograms per second)

FLOW .07 .07 .06 .06 .055 .05 .05 .045 .036 .031 .02

HEAD 35 60 70 80 90 100 110 120 130 140

produces the following coefficients

B( 1) = 0.700576E-01 b(l)

B( 2) = 0.393806E-03 b(2) x p

B( 3) = -0.168848E-04 b(3) x p"2

B( 4) = 0.171071E-06 b(4) x p"3

B( 5) = -0.634662E-09 b(5) x p"4

which correlates with the original data as

CALCULATED PERCENT

RES SURE FLOW FLOW DIFFERENCE

0.00 0.070 0.070 0.08

35.00 0.070 0.070 -0.66

60.00 0.060 0.062 2.71

70.00 0.060 0.058 -2.79

80.00 0.055 0.055 0.17

90.00 0.050 0.052 3.61

100.00 0.050 0.048 -3.61

110.00 0.045 0.044 -2.57

120.00 0.036 0.038 6.06

130.00 0.031 0.030 -1.69

140.00 0.020 0.020 -0.72

30
Example Calculation

EXAMPLE OF HYDROGEN CHLORIDE DEPOSITION AND MECHANICAL

VENTILATION

An example of the interaction of mechanical ventilation with hydrogen chloride

deposition (HCl) can be shown using the following data file:

VERSN 18 SSUl TIMES 180 30 TAMB 288. 101300. 0. HI/F 0.0 0.0 0.0 WIDTH 10.0 10.0 10. DEPTH 10.0 10.0 10. HEIGH 5. 5.0 5. HVENT 14 1 1.0 2. 1 0.0

HVENT 2 4 1 1.0 2. 1 0.0

HVENT 3 4 1 1.0 2. 1 0.0

CEILI OFF WB GLASS

FLOOR OFF WB GLASS WALLS OFF WB GLASS

LFBT 2 LFMAX 2 CHEMI 16. 50. 10. 10000000. 300. FMASS 0.05 0.05 0.05

FTIME 120. 1800.

HCL .1 .1 .1 CO .10 .10 .10 HCR 0. 0. 0. MVDCT 1 2 5. .15 .19E 3 3.30 .01767 0. 0. MVDCT 3 4 5. .15 .19E 3 2.94 .01767 0. 0. MVDCT 5 6 5. .15 .19E 3 3.30 .01767 0. 0. MVDCT 7 8 5. .15 .19E 3 2.94 .01767 0. 0. MVFAN 2 3 0.0 140. C).140 3.170E-04 -1.803E-05 1.898E-07 -8.104E-10 MVFAN 6 7 0.0 140. C).140 3.170E-04 -1.803E-05 1.898E-07 -8.104E-10 MVOPN 1 1 H 4.5 1. MVOPN 2 4 H 4.5 1. MVOPN 1 5 H 4.5 1. MVOPN 3 8 H 4.5 1. INELV 2 4.4 3 4.4 6 4.4 7 4.4

In this case, there are three compartments, each with a normal (HVENT) opening

only to the outside. The three compartments are connected to each other by mechanical

ventilation ducts. The compartment layout is shown in figure 3, with compartment #2 on the

left, compartment #1 in the center and compartment #3 on the right hand side of the figure.

The fire is in the center compartment (#1) and a pair of fans blows the fire gases into the

other two compartments (#2 and #3). The wall lining for the second compartment is wall

board, and for the third compartment glass. The two compartments are symmetric in that all openings to the outside are the same size and the fans have the same pressure curves, so flow

will be the same to both sides. The fire is small, and the pyrolyzate contains 10% hydrogen

chloride, to emphasize the effect of mechanical ventilation and deposition.

31
Reflnement of a Model for Fire Growth and Smoke Transport

1x2.1 5m 1x2.1

1 1 #1

5 m < >\

1x2.1

• ' * ^

1 '

'

1 #3

/

1

1 E #2 <=

^

=> =>

o

' r 4

10m

Fan Coef. ( 6 p)

0.14

3x10-4

3. -1.8x10-^

4. 1.8x10-6

5. -8.1x10-''°

Figure 3. Plan diagram of the geometry used in the HCl deposition calculation.

Figure 4 shows the difference in the HCl concentration in the lower layer of the two

compartments not containing the fire. If wall adsorption 34 were not important, then the

concentrations of HCl in the two gas layers would be the same. As can be seen, the

deposition onto the wall is influenced by the concentration in the environment, with the HCl

concentration lower in the room which is lined with gypsum.

32
Example Calculation

60

E

a.

a.u

sz Q.

2 L HCL

3 L HCL

10

100

TIME (s)

Figure 4. HCL concentration in the lower layer of compartments 2 and 3.

200

33
Refinement of a Model for Fire Growth and Smoke Transport

6. ERRATA for "Technical Reference Guide for FAST Version 18"

Page 13 has an incorrect power in the second line of the entrainment region

change intermittent: to intermittent:m^Q = 0.026 (Z/Q2/5)1 85 q.OS ^ Z/Q^^ ^ 0.20

m^Q = 0.026 (Z/Q2/')0^ 0.08 ^ Z/Q^^ ^ 0.20

Page 40, section 5.5, the conversion coefficient from fuel (pyrolysatc) to carbon dioxide was

specific for methane. The form has been changed to reflect a general fuel.

del

change

to

change

to

change

to

OOSTOK = 13200000. / HCOMBA

QPYROL

QPYROL

NETFUL

NETFUL

NET02

MAX(0. ,MIN(PYROL, 00ST0K*02MASS) ) * HCOMBA

MAX (0., MIN(PYROL*HCOMBA, 02MASS*02F))

- NETFUEL NET02

- NETFUEL

- QPYROL * 02F (o2f = 1.32x10^)

- QPYROL / 1.32E+7

NETC02 = 3.67 * NETFUEL

/( (1+HCRATT)*(1 .+1 . 57*C0C02T+3 . 67*CC02T)

)

FACTOR = (l.+HC0MBA*02FI)-9.*HCRATT/(l+HCRATT) (o2fi=7.578xio-8)

NETC02 = FACTOR * NETFUEL / (1 .+COC02T+CC02T)

Page 49, section 6.1

Label Parameter Comments

VERSN (2) ...

Version ... in columns 8-10. Number

Page 73, section 6.10

LABEL (10)

Label

Number

34
Errata

Text

after Text and before Anglel, AngleZ, insert

Color color number (0-15)

Anglel,

Angle2

35
Refinement of a Model for Fire Growth and Smoke Transport

7. NOMENCLATURE

The variables used in the formulae are listed here. There are a few exceptions for

local variables which are used only in a section for expository purposes. In general, most of

these variables can be indexed by compartment (single i) or by the layer in a given

compartment (u or {). The variables shown in the implementation section correspond roughly

to the mathematical variables shown here. Due to the limitations of character sets for

computers, there can not be an exact correspondence, but the crosswalk should be clear. The

first list is for the earlier discussion. The next list is for the numerical model as it is currently

implemented.

Variables used in the mathematical description of the model:

Ao - area of a mechanical ventilation duct (m*^)

A^ - area of a boundary, such as the ceiling, floor (m*^)

Cq - flow coefficient (nondimensional)

CO2, CO, HCl, HCN, S(soot), HjO - species production during pyrolysis

H, C, O - composition weight of the fuel - used only as a fraction H/C,...

HCl/C, HCN/C, HCN/f and HCl/f - ratio of species to carbon or fuel production (kg/kg)

fj - algebraic form of conservation of mass in a duct

F - friction factor (dimensionless)

f/C - fuel carbon production ratio (^1)

G - conductance for mass flow

hj. - heat of combustion

kj. - transport coefficient for HCl (m/s)

kg - equilibrium coefficient for HCl (m)

k, - wall loss rate for HCl (s"^)

Amo(actual) - the change of fuel during a time step

mpiQ - total mass of hydrogen chloride in a layer (kg)

<^HCi,w " mass density of hydrogen chloride on a wall surface (kg/m')

rii - time rate of change of a mass; this is the time equivalent of Am

Amf - change in the mass of fuel for an interval of time

36
Nomenclature

Arric - change in available carbon (see comment on fuel)

Am^Qj - change in species xx, where xx is one of COo, CO, HCl, HCN, S(soot), HjO

P - pressure (Pa)

AQ - heat released by a change in fuel (J)

Tg - gas temperature (K)

T^ - wall temperature (K)

V - volume of a zone (layer)

Phci n^ass density of hydrogen chloride in the gas phase (kg/m^)

pg - mass density of a gas layer (kg/m^)

PbiHci " n^3ss density of HCl in the boundary layer (kg/m^)

^xx^

lyyj

is used for the mass ratio of a species xx to yy.

This can refer to the properties of the fuel, which is reflected in the pyrolysis, or the

production of species from burning.

37
Reflnement of a Model for Fire Growth and Smoke Transport

8. REVISION HISTORY

This is an annotated list of changes for the various versions from 18.0 to the current

version, 18.5.2.

Version 18.5.1 - March 3, 1990.

The input routine (and the size of the common block) have been changed so that the HCl

data for wall absorption is now picked up from the thermophysical properties file. The routine

"CHEMIE" has been changed to incorporate the complete chemistry scheme as shown in the

revision document. A key word that has been added is 02 which is the oxygen/carbon ratio in the fuel. Both chlorine and oxygen content of the fuel are reflected in the actual amount of

pyrolysate available for combustion. A new module has been added called "CF_rpt." It will read the dump file produced by E\ST or E\ST_in and generate a report. The codes are fetched with the option /r and are

1 configuration (B.l)

2 normal output (B.2)

4 flow

8 species (B.2)

16 fed type 1 (see the Hazard Technical Reference Manual) [8]

32 fed type 2 &3

The codes can be combined. For example, /rll yields the usual output from FAST, whereas

/r3 would show on the configuration information. The command is

CF_rpt/rll xxx.dmp,

which would generate a list as shown in the Technical Reference Guide[l].

The "bug" noted below for monochrome CGA monitors has been fixed.

There is a bug in FASTJn in the section which sets the open/close parameters for vents. The

problem arises if there are more vents than can be listed on the page (8), and one scrolls down the list and then back up. If one them attempts to set the open/close parameters, the

vent retrieved is not the one pointed to by the inverse bar.

Version 18.5.0 - February 1, 1990.

Several changes were made to the routine that calculates the source terms for the solver.

First, Hydrogen chloride deposition onto walls was added. The transfer coefficients arc put

38
Revision History

the in the thermophysical data; second, an error in the mass flow which occurs in certain cases was corrected. The problem arose when the natural stack effect was important, specifically if hot air entered near the floor in the summer time, or very cold air near the top in the winter;

third, mechanical ventilation was added; finally, we have a place holder for smoke

agglomeration and deposition. The overlay for this release is 185.

The relevant key words for the mechanical ventilation are MVOPN, MVDCT, MVFAN AND INELV

There is a known bug which will not be fixed until the next release. It occurs on monochrome monitors with cga or lower resolution. The problem arises when running the

graphics mode of FAST, or FASTplot.

The wall absorption coefficients are wired into the code for gypsum. The correct data is in the THERMAL.TPF file but is not picked up. This too will be fixed in the next release. It will involve a change in the size of the dump files. The other coefficients, for boundary layer

transfer,... are picked up correctly from the database.

Version 18.4.2 - October 3, 1989.

There was a bug in FAST_in which did not generate the correct value for the relative

humidity in the output file. It was used correctly within each of the separate models (FAST

and FAST_in), and could be set separately in the data file.

Version 18.4.1 - September 14, 1989.

The factor for conversion from pyrolysate to COj was changed. The value in the

technical reference is correct only for methane. The change was in CHEMIE and is NETC02 = 3.67 * NETFUEL / ((l+HCRATT)*(l. + 1.57*COC02T+3.67*CC02T))

becomes

FACTOR = (1.+HCOMBA/1.32E+7) - 9.*HCRATT/(1.+HCRATT)

NETC02 = FACTOR * NETFUEL / ((l+HCRATT)*(l.+COC02T+CC02T))

PYROLS was changed to place a limit on the H/C ratio to 1/3, the value for

methane. This is a mass ratio, 4x1/12-1/3.

The default for the ignition temperature in vent flow was set to

pyrolysis temperature + 100 K.

This prevents spurious calculations when the layers are at ambient conditions.

39
Reflnement of a Model for Fire Growth and Smoke Transport

This is an arbitrary choice. Any value above the highest ambient condition

is sufficient, and can be set with the CHEMIE entry. Species information is included in the

normal listing only if the "-print interval" switch is set. This is also the option to see the flow

field.

The executable for the FAST module was split into two pieces, EAST.EXE

and EAST. 184, to conform with the Hazard I release format.

Any value above the highest ambient temperature is sufficient, and can be set with the

"CHEMIE" entry. Species information is included in the normal listing only if the "-print

interval" switch is set. This is also the option to sec the flow field. The executable for the

E\ST module was split into two pieces, EAST.EXE and FAST. 184, to conform with the

Hazard I release format. The corresponding version of FASTplot is 4.1 and FAST_in is 2.4.

Version 18.4.0 - July 1, 1989.

The outside boundary condition for the heat transfer thru walls was modified in CNDUCT to account for radiation from the walls:

after

QDOUTL = - QDOUTL

add

+ SIGM*EPW(NWW,NC)*(TWJ(NWW,NC,NT0T)**4-TWE(NWW,NC)**4).

Several changes were made to the routine that calculates the source terms for the solver.

First, Hydrogen chloride deposition onto walls was added. The transfer coefficients are put in the thermophysical data. Second, an error in the mass flow which occurs in certain cases was

corrected. The problem arose when the natural stack effect was important, specifically if hot

air entered near the floor in the summer time, or very cold air near the top in the winter. The

changes were made in DSOURC, the control program as follows:

+ (TU(J)-TU(I)) * (SSIN+SAIN) + (TL(J)-TL(I)) * (ASIN+AAIN)

became

+ (TU(J)-TU(I)) * INULU

+ (TL(J)-TU(I)) * INULL

+ (TL(J)-TU(I)) * INLLU

+ (TL(J)-TL(I)) * INLLL

40
Revision History

Third, mechanical ventilation was added. Finally, a place holder for smoke agglomeration and

deposition was inserted. The relevant key words for the mechanical ventilation are mvopn,

mvdct, mvfan and inelv.

The routine (lenoco) which finds the size of the common block was made some what more

general so that dump files from earlier runs would be accessible, and version 4.1 of FASTplot

can read the dump files from version 18.3.

The input routines (NPUTP, NPUTPR, NPUTQ and NPUTQR) were combined into NPUTP

and NPUTQ. The other two, which were used for restarts, are now eliminated, which does

two things, first it makes updates easier, and second will allow (eventually) restarts from

FASTJn.

The species transport was updated to conform with the mass flow as calculated in the source

routines. Previously, the same error which is described above for certain cases of stack effect

would cause the same problems in the species transport.

The calculation of "target" was corrected from

60 ONTARGET(I) = SIGM * (P(I+N) -TAMB(I) )'-"'t4

to

60 ONTARGET(I) = SIGM * (P(I+N)->>^-4-TAMB(I)**4)

in the routine toxic.

The modules testga.exe and tequipt.exe have been replaced by list_fcg.exe.

Disk #4, which contained the build and system*.fnt files is no longer included. The Build

module is in the process of begin revised extensively, and will be reissued when it is finished.

The executable for the FAST module was split into two pieces, FAST.EXE and FAST. 184, to conform with the Hazard I release format.

Version 18.3.3 - June 30, 1989.

The parameter "inter" was not passed correctly between the code which reads the ASCII data

file and the initialization routine, so it was not possible to set the interface at any point other

than the top of the compartment. FASTplot was fixed so that when no data is present, the

graphics routines will not quit in an unfriendly manner, as they sometimes did prior to 4.0. FASTJn now requires that an alternate installation procedure be done to enable the

advanced features, which include the ability to do computations within the data editor itself. See Technical Note 1262 for details.

41
Reflnement of a Model for Fire Growth and Smoke Transport

All of the routines which use the graphics mode now reset the lookup table (palette) to the

values in use prior to executing a program upon termination.

Version 18.3.2 - February 1, 1989.

For FAST, the time for output was fixed so that output for restarts is calculated relative to the beginning of the restart rather than time 0. This allows for 50 intervals for each restart rather than 50 for the entire simulation. In FASTjn, the key prompt in the calculation screen does not show a "key" command, since this would be superfluous. Also, the length of

the thermal names was put back to 8 characters. During optimization of the code, this was

inadvertently truncated to 5 characters. The version number for FAST_in is 2.1 The

parameter "TGIGNT' was added to the "CHEMI" line to specify the conditions for ignition of

a gas. Below this temperature, a fuel/oxygen mixture will not burn, and above this limit, it will

burn depending on the usual burning rate scheme.

Version 18.3.1 - November 14, 1988.

Added the key words "THRMP and "DEFCG" to the input file to specify an alternate

thermophysical data base, and configuration file from within the data file itself. Multiple

layers in the thermophysical properfies are now displayed. The limit on the oxygen index has

been changed from

02MASS = 02ENTR * 02 INDEX

to 02MASS = 02ENTR * 0.995 * (1 . -EXP( - 10 . ^-02INDEX)

)

which more closely represents what actually occurs in the kinetics process. The boundary

conditions on the ceiling and floor to the ambient have been reversed. They are stated

correctly in the journal article and the User's Guide, but were implemented for the outside

the same way they were done on the interior walls in the model. This has been reversed.

The ceiling now behaves as a floor on outside, and the floor behaves as a ceiling.

FAST now stops if it can not find the thermal properties which have been requested in the

data file. FAST_in does not stop, but rather sets the corresponding values to "NONE." Two

parameters have been added to the CHEMIE line. The sixth element is an ignition

temperature and the seventh is the fraction of heat from the fire which is radiated rather than

convected away. Default for the ignition temperature is the volatilization temperature and

zero for the radiative fraction.

Relative humidity now sets the water content of the atmosphere by

DT = TAMB(I) - 273.

DP = ((36.6 + 3.54*DT + . l*DT^"*2)/760 . ) * (18./28.4)

02N2(8) = RELHUM * DP.

42
Revision History

These factors are fitted to a table of values in the Handbook of Chemistry and Physics. The

corresponding versions are FASTplot v 3.6.4 and FASTin v 2.0.

Version 18.3.0 - October 16, 1988.

A type two fire limits burning (not pyrolysis) based on the available oxygen. FASTplot version

3.6.2 fixes a bug in the "clear" command when interacting with RAPID files. Entrainment into

the upper layer via a plume has a limitation based minimum buoyancy. The source terms are

reset for each pass of the source routine (DSOURC) so that the fire room can be moved.

With FAST this must be done with a restart, but with FASTin, the model can be stopped,

the fire moved, and the model restarted. The base system has been expanded to four disks to contain all the modules. One of these disks contains only the program BUILD, which is used

to generate the ".PIC" files for the real time display. If it is not needed, then BUILD.EXE

and SYSTEMnn.FNT can be deleted. FAST_in (v2.0) is official with this release.

Version 18.2.1 - July 30, 1988.

FASTplot (3.4) incorporates dashed/colored lines. The selection is through the DEFAULT

key word. The appropriate setting is the "axes format."

Version 18.2.0 - May 16, 1988.

A bug in the opening/closing routine has been fixed. This has necessitated a modification in the common block, but does not affect the interaction of FAST and FASTplot. The

corresponding version of FASTplot is 3.3 although 3.2 will work. FASTplot 3.3 works more

smoothly now. Also, a provision is in place for substituting line types for colors in the plots,

and changing devices, i.e. for pen plotters and laser printers. These are not implemented yet,

but some of the commands to utilize these devices will appear in "default" and "help."

Version 18.1.0 - May 5, 1988.

The connection between the inside compartments and the outside ambient was changed so

that each compartment could see a different outside. This allows the stack effect to work

properly. Also a different wind speed vector is calculated for each opening to the outside

world. Finally, a new key word('INTER') has been added to specify the initial position of the

interface inside a compartment. This is applicable primarily for studying the effect of summer

over winter in building flows. The corresponding version of FASTplot is 3.2.

The primary change in the inside-outside interaction was a change in the selection rules for

flow. In order to get both summer and winter flows to behave in a reasonable way, the

selection rules for vent flow have been modified. The selection rules for directing mass flow

through vents in FAST is fairly simple. Upper layer goes to upper layer, and lower layer to lower layer. This follows the prescription of Tanaka, which is actually quite simple and

elegant. We have improved greatly on the means of calculating the actual flow, but have kept

43
Reflnement of a Model for Fire Growth and Smoke Transport

this prescription. However, the predictions for the stack effect have turned up some

anomalies in this scheme. Thus the selection rules for flow have been modified. There are

six combinations based on the temperature of the source and receiving compartments.

Version 18.0 - February 8, 1988.

Add the opening/closing parameter CVENT and vitiated combustion. This latter change

require a change in "chemi". Corresponding changes were made in FASTplot (3.1) to accommodate the extra data.

44
References

9. REFERENCES

[1] Jones, W. W. and Peacock, R. D., Technical Reference Guide for FAST Version

18, NIST Technical Note 1262, 1989.

[2] Jones, W. W, A Multicompartment Model for the Spread of Fire, Smoke and

Toxic Gases, Fire Safety Journal 9, 55 (1985).

[3] Galloway, F. M. and Hirschler, M. M., A Model for the Spontaneous Removal of

Airborne Hydrogen Chloride by Common Surfaces, Fire Safety Journal 14, 251-

268 (1989).

[4] Galloway, F. M. and Hirschler, M. M., Transport and Decay of Hydrogen

Chloride: Use of a Model to Predict Hydrogen Chloride Concentrations in Fires

Involving a Room-Corridor-Room Arrangement, Fire Safety Journal 16, 33-52

(1990).

[5] Klote, J. H., A Computer Model of Smoke Movement by Air Conditioning

Systems, NBSIR 87-3657 (1987).

[6] 1989 ASHRAE Handbook Fundamentals, American Society of Heating,

refrigeration and Air Conditioning Engineers, Inc., Atlanta, Georgia (1989).

[7] Abramowitz, M and Stegun, I., Handbook of Mathematical Functions, National

Bureau of Standards Applied Mathematics Series 55 (1964).

[8] Hazard I Technical Reference Guide, NIST Special Publication 146 Volume II (1989).

45
Reflnement of a Model for Fire Growth and Smoke Transport

10. ACKNOWLEDGMENTS

The procedures we followed to include the mechanical ventilation and hydrogen chloride

ventilation is the paradigm for improving our models that will be used for the unified model at the Center for Fire Research. Several people contributed to the incorporation of the

algorithms in the manner that we would like to see. For the mechanical ventilation, J. Klote,

who was responsible for the SMACS model, was helpful with advice in using his algorithm.

For the hydrogen chloride deposition model, N. Bryner did an independent review, and M.

Galloway did the actual programming. Funding for this revision of the FAST model suite was

provided in part by the Naval Research Laboratory and the Vinyl Institute.

46
NIST-114A

(REV. 3-89) U.S. DEPARTMENT OF COMMERCE

NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY

BIBLIOGRAPHIC DATA SHEET

1. PUBUCATION OR REPORT NUMBER

NIST/TN-1282

2. PERFORMING ORGANIZATION REPORT NUMBER

3. PUBUCATION DATE November 1990

4. TITLE AND SUBTITLE

Refinement of a Model for Fire Growth and Smoke Transport

S. AUTHOR (S) Walter W. Jones

6. PERFORMING ORGANIZATION (IF JOINT OR OTHER THAN NIST, SEE INSTRUCTIONS)

U.S. DEPARTMENT OF COMMERCE

NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY

GAITHERSBURQ, MD 20899

7. CONTRACT/GRANT NUMBER

8. TYPE OF REPORT AND PERIOD COVERED

Final

9. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (STREET, CITY, STATE, ZIP)

San^e as item #6

10. SUPPLEMENTARY NOTES

DOCUMENT DESCRIBES A COMPUTER PROGRAM; SF-185, FIPS SOFTWARE SUMMARY, IS ATTACHED.

11. ABSTRACT (A 200-WORD OR LESS FACTUAL SUMMARY OF MOST SIGNIFICANT INFORMATION. IF DOCUMENT INCLUDES A SIGNIFICANT BIBUOGRAPHY OR

UTERATURE SURVEY, MENTION IT HERE.)

This document describes the changes which have occurred in FAST, FASTPLOT, FAST_ in and the

distribution disks in the change from 18.3, the release for Hazard I, and the current release

18.5. Included are an errata section for the Technical Note 1262, a revision history that

is distributed with the release disks, the addendum to the Technical Note for the new key

words, and the description of the implementation of the physical routines.

12. KEYWORDS (6 TO 12 ENTRIES; ALPHABETICAL ORDER; CAPITAUZE ONLY PROPER NAMES; AND SEPARATE KEY WORDS BY SEMICOLONS)

compartment fires; fire growth; mathematical models; numerical models; room fires;

smoke; toxicity

13. AVAILABIUTY UNUMITED

FOR OFFICIAL DISTRIBUTION. DO NOT RELEASE TO NATIONAL TECHNICAL INFORMATION SERVICE (NTIS). X

X ORDER FROM SUPERINTENDENT OF DOCUMENTS, U.S. GOVERNMENT PRINTING OFFICE, WASHINGTON, DC 20402. ORDER FROM NATIONAL TECHNICAL INFORMATION SERVICE (NTIS), SPRINGFIELD, VA 22161.

14. Nl'MBER OF PRINTED PAGES

50

15. PRICE

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