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TALK=T;RUN(1,1)
DISPLAY
Radiative heat transfer takes place between parallel flat
wide surfaces. The medium between them is at rest, and can
absorb, emit and scatter radiation, as well as conducting
heat.

Wall temperatures and emissivities are prescribed.

The solved-for variables are enthalpy, H1, and the composite
radiation fluxes in the +X and -X directions.

RADX has a diffusivity which depends on the scattering and
absorption coefficients.

The wall boundary condition for RADX has a Value equal to the
gross radiation flux emitted by the wall; thus the net flux is
proportional to:
The COefficient for RADX is a function of emissivity.
The locally-defined parameters are as follows:
GSIGMA         Stefan-Boltzmann constant
SCAT           Scattering coefficient
ABSORB         Absorption coefficient
EMIH           emissivity of the hot wall
EMIC           emissivity of the cold wall
THOT           hot wall temperature
TCOLD          cold wall temperature
ENDDIS
************************************************************
Group 1. Run Title and Number
************************************************************
************************************************************

TEXT(1D Radiant Heat Transfre In A Box       )

************************************************************
************************************************************

IRUNN = 1 ;LIBREF = 14
************************************************************
Group 2. Time dependence
************************************************************
Group 3. X-Direction Grid Spacing
CARTES = T
NX = 20
XULAST =1.
XFRAC(1)=0.015811 ;XFRAC(2)=0.044721
XFRAC(3)=0.082158 ;XFRAC(4)=0.126491
XFRAC(5)=0.176777 ;XFRAC(6)=0.232379
XFRAC(7)=0.292831 ;XFRAC(8)=0.357771
XFRAC(9)=0.426907 ;XFRAC(10)=0.5
XFRAC(11)=0.573092 ;XFRAC(12)=0.642229
XFRAC(13)=0.707169 ;XFRAC(14)=0.767621
XFRAC(15)=0.823223 ;XFRAC(16)=0.873509
XFRAC(17)=0.917842 ;XFRAC(18)=0.955279
XFRAC(19)=0.984189 ;XFRAC(20)=1.
************************************************************
Group 4. Y-Direction Grid Spacing
NY = 1
YVLAST =1.
YFRAC(1)=1.
************************************************************
Group 5. Z-Direction Grid Spacing
PARAB = F
NZ = 1
ZWLAST =1.
ZFRAC(1)=1.
************************************************************
Group 6. Body-Fitted Coordinates
************************************************************
Group 7. Variables: STOREd,SOLVEd,NAMEd
ONEPHS = T
* Y in SOLUTN argument list denotes:
* 1-stored 2-solved 3-whole-field
* 4-point-by-point 5-explicit 6-harmonic averaging
SOLUTN(H1,Y,Y,N,N,N,Y)
************************************************************
Group 8. Terms & Devices
* Y in TERMS argument list denotes:
* 1-built-in source 2-convection 3-diffusion 4-transient
* 5-first phase variable 6-interphase transport
TERMS(H1,N,N,Y,Y,Y,Y)
DIFCUT =0.5 ;ZDIFAC =1.
GALA = F ;ADDDIF = F
ISOLX = -1 ;ISOLY = -1 ;ISOLZ = -1
************************************************************
Group 9. Properties used if PRPS is not
stored, and where PRPS = -1.0 if it is!
RHO1 =1. ;TMP1 = GRND2
EL1 =0.
TSURR =0. ;TEMP0 =0.
PRESS0 =0.
DVO1DT =0. ;DRH1DP =0.
TMP1A =0. ;TMP1B =1.
TMP1C =0.
TMP2A =0. ;TMP2B =0.
TMP2C =0.
EMISS =0. ;SCATT =0.
ENUL =1.0E-03 ;ENUT =0.
CP1 =1. ;CP2 =1.
************************************************************
Group 10.Inter-Phase Transfer Processes
************************************************************
Group 11.Initial field variables (PHIs)
No PATCHes yet used for this Group
FSWEEP = 1
NAMFI =CHAM
************************************************************
Group 12. Patchwise adjustment of terms
Patches for this group are printed with those
for Group 13.
Their names begin either with GP12 or &
************************************************************
Group 13. Boundary & Special Sources

PATCH(RADISO ,FREEVL, 0, 0, 0, 0, 0, 0, 1, 1)
COVAL(RADISO ,H1 , GRND1 , GRND1 )

PATCH(WESTR ,WEST , 1, 1, 1, 1, 1, 1, 1, 1)

PATCH(EASTR ,EAST , 20, 20, 1, 1, 1, 1, 1, 1)

PATCH(WESTH ,WWALL , 1, 1, 1, 1, 1, 1, 1, 1)
COVAL(WESTH ,H1 ,1. ,600. )

PATCH(EASTH ,EWALL , 20, 20, 1, 1, 1, 1, 1, 1)
COVAL(EASTH ,H1 ,1. ,300. )
XCYCLE = F
EGWF = T
WALLCO = GRND2
************************************************************
Group 14. Downstream Pressure For PARAB
************************************************************
Group 15. Terminate Sweeps
LSWEEP = 25 ;ISWC1 = 1
LITHYD = 1 ;LITFLX = 1 ;LITC = 1 ;ITHC1 = 1
SELREF = T
RESFAC =1.0E-04
************************************************************
Group 16. Terminate Iterations
************************************************************
Group 17. Relaxation
RELAX(H1,FALSDT,0.04)
OVRRLX =0.
EXPERT = F ;NNORSL = F
************************************************************
Group 18. Limits
VARMAX(H1)=1.0E+10 ;VARMIN(H1)=-1.0E+10
************************************************************
Group 19. Data transmitted to GROUND
PARSOL = F
ISG62 = 1
************************************************************
Group 20. Preliminary Printout
************************************************************
Group 21. Print-out of Variables
INIFLD = F ;SUBWGR = F
* Y in OUTPUT argument list denotes:
* 1-field 2-correction-eq. monitor 3-selective dumping
* 4-whole-field residual 5-spot-value table 6-residual table
OUTPUT(H1,Y,Y,Y,Y,Y,Y)
************************************************************
Group 22. Monitor Print-Out
IXMON = 10 ;IYMON = 1 ;IZMON = 1
NPRMON = 100000 ;NPRMNT = 1 ;TSTSWP = -1
UWATCH = T ;USTEER = T
HIGHLO = F
************************************************************
Group 23.Field Print-Out & Plot Control
NPRINT = 100000 ;NUMCLS = 5
NXPRIN = -1 ;IXPRF = 1 ;IXPRL = 10000
IPLTF = 1 ;IPLTL = -1 ;NPLT = 2
ISWPRF = 1 ;ISWPRL = 100000
ITABL = 1 ;IPROF = 1
ABSIZ =0.5 ;ORSIZ =0.4
NTZPRF = 1 ;NCOLPF = 50
ICHR = 2 ;NCOLCO = 45 ;NROWCO = 20

PATCH(XWISE ,PROFIL, 1, 20, 1, 1, 1, 1, 1, 1)
PLOT(XWISE ,H1 ,0. ,0. )