```
TALK=T;RUN(1,1)
PHOTON USE
p;parphi
1 2.5 1 ;;;;

msg The grid. The z coordinate represents time
msg Press return for the pressure contours.
gr x 1;pause
gr off;red;gr ou x 1
msg pressure distribution. Press return for enthalpies
con p1 x 1 fi;0.1;pause;con off;red
msg enthalpy distribution. Press e to end, or type other command
con h1 x 1 fi;0.1
enduse
DISPLAY

The default settings are for a pipe with closed ends, and with
initially uniform-pressure and -temperature gas in uniform motion.

A series of intersecting pressure waves results, with
corresponding variations of enthalpy.

Other cases involve the gas initially at rest, and the presence
of time-varying boundary conditions at one end of the pipe. In one
case the pressure is fixed at an intemediate point.

Ideal-gas properties are used.

PHOTON USE commands are provided.

ENDDIS
************************************************************
Group 1. Run Title and Number
************************************************************
************************************************************

TEXT(GAS_AT_REST._SUDDEN_SUSTAINED_ENTRY_FROM)

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

IRUNN = 1 ;LIBREF = 14
************************************************************
Group 2. Time dependence
* Set overall time and no. of steps
TFIRST =0. ;TLAST =5.
FSTEP = 1 ;LSTEP = 500
TFRAC(1)=2.0E-03 ;TFRAC(126)=0.252
TFRAC(251)=0.502 ;TFRAC(376)=0.752
************************************************************
Group 3. X-Direction Grid Spacing
CARTES = T
NX = 1
XULAST =1.
XFRAC(1)=1.
************************************************************
Group 4. Y-Direction Grid Spacing
NY = 20
YVLAST =1.
YFRAC(1)=0.05 ;YFRAC(2)=0.1
YFRAC(3)=0.15 ;YFRAC(4)=0.2
YFRAC(5)=0.25 ;YFRAC(6)=0.3
YFRAC(7)=0.35 ;YFRAC(8)=0.4
YFRAC(9)=0.45 ;YFRAC(10)=0.5
YFRAC(11)=0.55 ;YFRAC(12)=0.6
YFRAC(13)=0.65 ;YFRAC(14)=0.7
YFRAC(15)=0.75 ;YFRAC(16)=0.8
YFRAC(17)=0.85 ;YFRAC(18)=0.9
YFRAC(19)=0.95 ;YFRAC(20)=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
NAME(1)=P1 ;NAME(5)=V1
NAME(14)=H1
* Y in SOLUTN argument list denotes:
* 1-stored 2-solved 3-whole-field
* 4-point-by-point 5-explicit 6-harmonic averaging
SOLUTN(P1,Y,Y,N,N,N,Y)
SOLUTN(V1,Y,Y,N,N,N,Y)
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(P1,Y,Y,Y,N,Y,Y)
TERMS(V1,Y,Y,Y,Y,Y,Y)
TERMS(H1,Y,Y,Y,Y,Y,Y)
DIFCUT =0.5 ;ZDIFAC =1.
GALA = F ;ADDDIF = F
NEWRH1 = T
HUNIT =1.
ISOLX = -1 ;ISOLY = -1 ;ISOLZ = -1
************************************************************
Group 9. Properties used if PRPS is not
stored, and where PRPS = -1.0 if it is!
RHO1 = GRND5 ;TMP1 = GRND2
EL1 =0.
TSURR =0. ;TEMP0 =0.
PRESS0 =1.
DVO1DT =0. ;DRH1DP =1.
RHO1A =0. ;RHO1B =1.
RHO1C =0.
TMP1A =0. ;TMP1B =0.285714
TMP1C =0.
TMP2A =0. ;TMP2B =0.
TMP2C =0.
EMISS =0. ;SCATT =0.
ENUL =1.0E-05 ;ENUT =0.
PRNDTL(V1)=1. ;PRNDTL(H1)=1.
PRT(V1)=1. ;PRT(H1)=1.
CP1 =3.5 ;CP2 =1.
************************************************************
Group 10.Inter-Phase Transfer Processes
************************************************************
Group 11.Initial field variables (PHIs)
FIINIT(P1)=0. ;FIINIT(V1)=0.
FIINIT(H1)=3.5
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(TIMN ,NORTH , 1, 1, 20, 20, 1, 1, 1, 500)
COVAL(TIMN ,P1 , FIXFLU , GRND1 )
COVAL(TIMN ,V1 ,0. ,-0.5 )
COVAL(TIMN ,H1 ,0. ,14.000001 )
XCYCLE = F
EGWF = T
WALLCO = GRND2
************************************************************
Group 14. Downstream Pressure For PARAB
************************************************************
Group 15. Terminate Sweeps
LSWEEP = 10 ;ISWC1 = 1
LITHYD = 1 ;LITFLX = 1 ;LITC = 1 ;ITHC1 = 1
SELREF = T
RESFAC =1.0E-03
************************************************************
Group 16. Terminate Iterations
LITER(P1)=20 ;LITER(V1)=10
LITER(H1)=20
ENDIT(P1)=1.0E-03 ;ENDIT(V1)=1.0E-03
ENDIT(H1)=1.0E-03
************************************************************
Group 17. Relaxation
RELAX(P1,LINRLX,1.)
RELAX(V1,FALSDT,1.)
RELAX(H1,FALSDT,1.0E+09)
OVRRLX =0.
EXPERT = F ;NNORSL = F
************************************************************
Group 18. Limits
VARMAX(P1)=1.0E+10 ;VARMIN(P1)=-1.0E+10
VARMAX(V1)=1.0E+06 ;VARMIN(V1)=-1.0E+06
VARMAX(H1)=1.0E+10 ;VARMIN(H1)=0.5
************************************************************
Group 19. Data transmitted to GROUND
PARSOL = F
IDISPB = 1 ;IDISPC = 500
ITIMA = 1000
ISG62 = 1
TIMA =0.5
************************************************************
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(P1,Y,N,Y,Y,Y,Y)
OUTPUT(V1,Y,N,Y,Y,Y,Y)
OUTPUT(H1,Y,N,Y,Y,Y,Y)
************************************************************
Group 22. Monitor Print-Out
IXMON = 1 ;IYMON = 1 ;IZMON = 1
NPRMON = 100000 ;NPRMNT = 1 ;TSTSWP = 10
UWATCH = T ;USTEER = T
HIGHLO = F
************************************************************
Group 23.Field Print-Out & Plot Control
NPRINT = 100000 ;NUMCLS = 5
NTPRIN = 125 ;ISTPRF = 1 ;ISTPRL = 100000
NYPRIN = 1 ;IYPRF = 1 ;IYPRL = 10000
IPLTF = 1 ;IPLTL = -1 ;NPLT = -1
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(PROFILES,PROFIL, 1, 1, 10, 10, 1, 1, 1, 500)
PLOT(PROFILES,P1 ,0. ,0. )
PLOT(PROFILES,V1 ,0. ,0. )
************************************************************
Group 24. Dumps For Restarts
SAVE = T ;NOWIPE = F
NSAVE =CHAM
IDISPA = 10 ;IDISPB = 1 ;IDISPC = 500
STOP
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