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TALK=T;RUN(1,1)
DISPLAY

MONO-PROPELLANT ROCKET COMBUSTION

2-dimensional (x-y), Cartesian, steady, two-phase, elliptic
simulation

The problem considered is that of the injection of monopropellant
droplets through small holes in one end of a rocket motor. These
droplets burn (i.e undergo a phase change involving the
disappearance of high-density liquid and its replacement by low-
density gas), at a rate dependent upon the droplet diameter. As a
consequence, a pressure gradient is set up which accelerates the
gas and, to a lesser extent, the liquid. Friction between the
droplets and the gas causes the former at first to deccelerate and
later to accelerate.

The model is highly idealised, and does not represent any
particular motor or propellant.

You will have an opportunity to vary the interphase-friction
coefficient and the injection velocity of the liquid.

enddis
PHOTON USE
p
phi

gr ou z 1
set vec comp
au1 cv1 -
msg Gas-velocity vectors
vec z 1 sh
msg Press  to continue
pause
vec off;red
set vec comp
bu2 dv2 -
msg Droplet-velocity vectors
vec z 1 sh
msg Press  to continue
pause
vec off;red
msg volume fraction of liquid
con liq z 1 sh;int 50
msg Press  to continue
pause
msg Note that the grid is very coarse
gr z 1
msg Press e to END
enduse
DISPLAY
The problem considered is that of the injection of monopropellant
droplets through small holes in one end of a rocket motor. These
droplets burn (i.e undergo a phase change involving the dis-
appearance of high-density liquid and its replacement by low-
density gas), at a rate dependent upon the droplet diameter. As a
consequence, a pressure gradient is set up which accelerates the
gas and, to a lesser extent, the liquid. Friction between the
droplets and the gas causes the former at first to deccelerate
and later a accelerate.
The main task is to compute the distance from the injector at
which the propellant is fully consumed, as functions: of the
injection velocity, of the propellant and combustion-product
properties, and of a measure of the relative speed of momentum
and heat transfer.
The GX-subroutine GXDROP is used for this case.
ENDDIS
************************************************************
Group 1. Run Title and Number
************************************************************
************************************************************

TEXT(Rock2; 2D MONOPROPELLANT ROCKET   :W971 )

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

IRUNN = 1 ;LIBREF = 14
************************************************************
Group 2. Time dependence
************************************************************
Group 3. X-Direction Grid Spacing
CARTES = T
NX = 10
XULAST =1.
XFRAC(1)=0.1 ;XFRAC(2)=0.2
XFRAC(3)=0.3 ;XFRAC(4)=0.4
XFRAC(5)=0.5 ;XFRAC(6)=0.6
XFRAC(7)=0.7 ;XFRAC(8)=0.8
XFRAC(9)=0.9 ;XFRAC(10)=1.
************************************************************
Group 4. Y-Direction Grid Spacing
NY = 10
YVLAST =0.5
YFRAC(1)=0.1 ;YFRAC(2)=0.2
YFRAC(3)=0.3 ;YFRAC(4)=0.4
YFRAC(5)=0.5 ;YFRAC(6)=0.6
YFRAC(7)=0.7 ;YFRAC(8)=0.8
YFRAC(9)=0.9 ;YFRAC(10)=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 = F
EQUVEL = F
NAME(1)=P1 ;NAME(3)=AU1
NAME(4)=BU2 ;NAME(5)=CV1
NAME(6)=DV2 ;NAME(9)=GAS
NAME(149)=CFIP ;NAME(150)=MDOT
* 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(AU1,Y,Y,N,N,N,Y)
SOLUTN(BU2,Y,Y,N,N,N,Y)
SOLUTN(CV1,Y,Y,N,N,N,Y)
SOLUTN(DV2,Y,Y,N,N,N,Y)
SOLUTN(LIQ,Y,Y,N,N,N,Y)
SOLUTN(CFIP,Y,N,N,N,N,Y)
SOLUTN(MDOT,Y,N,N,N,N,Y)
INTMDT = 150
************************************************************
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(AU1,Y,Y,N,Y,Y,Y)
TERMS(BU2,Y,Y,N,Y,N,Y)
TERMS(CV1,Y,Y,Y,Y,Y,Y)
TERMS(DV2,Y,Y,Y,Y,N,Y)
TERMS(LIQ,Y,Y,N,Y,N,Y)
DIFCUT =0.5 ;ZDIFAC =1.
GALA = F ;ADDDIF = F
EQDVDP = 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 =10. ;TMP1 =0.
EL1 =0.
TSURR =0. ;TEMP0 =0.
PRESS0 =1.0E+07
DVO1DT =0. ;DRH1DP =0.
EMISS =0. ;SCATT =0.
RHO2 =1.0E+04 ;TMP2 =0.
EL2 =0.
DVO2DT =0. ;DRH2DP =0.
ENUL =1.0E-05 ;ENUT =0.
PHINT(AU1)=-2.022E+04 ;PHINT(BU2)=-2.022E+04
PHINT(CV1)=-2.022E+04 ;PHINT(DV2)=-2.022E+04
PRNDTL(CV1)=1. ;PRNDTL(DV2)=1.
PRT(CV1)=1. ;PRT(DV2)=1.
CP1 =1. ;CP2 =1.
************************************************************
Group 10.Inter-Phase Transfer Processes
CFIPS = GRND1
RLOLIM =1.0E-09 ;CMDOT =1.
CFIPA =0. ;CFIPB =0.
CFIPC =1.0E+05 ;CFIPD =0.
CINT(P1)=1. ;CINT(AU1)=1.
CINT(BU2)=1. ;CINT(CV1)=1.
CINT(DV2)=1. ;CINT(LIQ)=1.
PHINT(P1)=-2.022E+04 ;PHINT(AU1)=-2.022E+04
PHINT(BU2)=-2.022E+04 ;PHINT(CV1)=-2.022E+04
PHINT(DV2)=-2.022E+04 ;PHINT(LIQ)=-2.022E+04
************************************************************
Group 11.Initial field variables (PHIs)
FIINIT(P1)=1.0E-10 ;FIINIT(AU1)=50.
FIINIT(BU2)=50. ;FIINIT(CV1)=1.0E-10
FIINIT(DV2)=1.0E-10 ;FIINIT(GAS)=0.999
FIINIT(CFIP)=1.0E-10 ;FIINIT(MDOT)=10.
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(INLET ,WEST , 1, 1, 1, 5, 1, 1, 1, 1)
COVAL(INLET ,AU1 ,0. ,0. )
COVAL(INLET ,BU2 ,0. ,50. )
COVAL(INLET ,CV1 ,0. ,0. )
COVAL(INLET ,DV2 ,0. ,0. )
COVAL(INLET ,GAS , FIXFLU ,0. )
COVAL(INLET ,LIQ , FIXFLU ,2000. )

PATCH(OUTLET ,CELL , 10, 10, 1, 5, 1, 1, 1, 1)
COVAL(OUTLET ,AU1 ,0. ,0. )
COVAL(OUTLET ,BU2 ,0. ,0. )
COVAL(OUTLET ,GAS ,1. ,0. )
COVAL(OUTLET ,LIQ ,1000. ,0. )
XCYCLE = F
EGWF = T
WALLCO = GRND2
************************************************************
Group 14. Downstream Pressure For PARAB
************************************************************
Group 15. Terminate Sweeps
LSWEEP = 200 ;ISWC1 = 1
LITHYD = 1 ;LITFLX = 1 ;LITC = 1 ;ITHC1 = 1
ISWR1 = 1 ;ISWR2 = 10000
SELREF = T
RESFAC =1.0E-02
************************************************************
Group 16. Terminate Iterations
LITER(P1)=20 ;LITER(AU1)=10
LITER(BU2)=10 ;LITER(CV1)=10
LITER(DV2)=10 ;LITER(LIQ)=1
ENDIT(P1)=1.0E-03 ;ENDIT(AU1)=1.0E-03
ENDIT(BU2)=1.0E-03 ;ENDIT(CV1)=1.0E-03
ENDIT(DV2)=1.0E-03 ;ENDIT(LIQ)=1.0E-03
************************************************************
Group 17. Relaxation
RELAX(P1,LINRLX,1.)
RELAX(AU1,FALSDT,0.02)
RELAX(BU2,FALSDT,0.02)
RELAX(CV1,FALSDT,2.0E-03)
RELAX(DV2,FALSDT,2.0E-03)
RELAX(GAS,LINRLX,1.)
RELAX(LIQ,LINRLX,0.2)
RELAX(CFIP,LINRLX,1.)
RELAX(MDOT,LINRLX,1.)
OVRRLX =0.
EXPERT = F ;NNORSL = F
************************************************************
Group 18. Limits
VARMAX(P1)=1.0E+10 ;VARMIN(P1)=-1.0E+10
VARMAX(AU1)=1.0E+06 ;VARMIN(AU1)=-1.0E+06
VARMAX(BU2)=1.0E+06 ;VARMIN(BU2)=-1.0E+06
VARMAX(CV1)=1.0E+06 ;VARMIN(CV1)=-1.0E+06
VARMAX(DV2)=1.0E+06 ;VARMIN(DV2)=-1.0E+06
VARMAX(GAS)=1. ;VARMIN(GAS)=1.0E-06
VARMAX(LIQ)=1.0E-03 ;VARMIN(LIQ)=1.0E-09
VARMAX(CFIP)=1.0E+10 ;VARMIN(CFIP)=-1.0E+10
VARMAX(MDOT)=1.0E+10 ;VARMIN(MDOT)=-1.0E+10
************************************************************
Group 19. Data transmitted to GROUND
PRTSIZ = T
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(P1,Y,N,Y,Y,Y,Y)
OUTPUT(AU1,Y,N,Y,Y,Y,Y)
OUTPUT(BU2,Y,N,Y,Y,Y,Y)
OUTPUT(CV1,Y,N,Y,Y,Y,Y)
OUTPUT(DV2,Y,N,Y,Y,Y,Y)
OUTPUT(GAS,N,N,N,N,N,N)
OUTPUT(LIQ,Y,N,Y,Y,Y,Y)
OUTPUT(CFIP,Y,N,Y,N,N,N)
OUTPUT(MDOT,Y,Y,Y,Y,Y,Y)
************************************************************
Group 22. Monitor Print-Out
IXMON = 5 ;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 = 0 ;IXPRF = 1 ;IXPRL = 10000
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(XPROFILE,PROFIL, 1, 10, 1, 1, 1, 1, 1, 1)
PLOT(XPROFILE,AU1 ,-1. ,-1. )
PLOT(XPROFILE,BU2 ,-1. ,-1. )
PLOT(XPROFILE,LIQ ,0. ,0. )