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TEXT(Boiling 2-Phase Flow in S-bend Duct:W886
TITLE
DISPLAY
This case simulates the steady flow of a two-phase mixture in a
2-D duct, with heated walls.

The mixture has uniform composition at inlet; but the distribution
changes with distance downstream, for two reasons, namely:-

1. the denser fluid moves to the outside of the bends; and
2. dense fluid changes into light, through boiling near the
heated walls.

the following question.

This Q1 contains PHOTON USE commands.
ENDDIS
GROUP 1. Run title
REAL(REYNO,WIN,DIAM)
REYNO=3.E3;DIAM=.3;WIN=1.0
REYNO
GROUP 6. Body-fitted coordinates or grid distortion
BFC=T;NONORT=T
L1=1;L2=1;L3=1
NZ1=6;NZ2=10;NZ3=6;NZ4=10;NZ5=6
NZ=NZ1+NZ2+NZ3+NZ4+NZ5

GSET(D,1,10,NZ,0.1,DIAM,1)
IZ2=NZ1+1

GSET(C,K:IZ2:,F,K1,+,0,0,L1,INC,-1.5)
IZ1=IZ2;IZ2=IZ1+NZ2

IZ1=IZ2;IZ2=IZ1+NZ3

GSET(C,K:IZ2:,F,K:IZ1:,+,0,0,-L2,INC,S1.5)
IZ1=IZ2;IZ2=IZ1+NZ4

IZ1=IZ2;IZ2=IZ1+NZ5

GSET(C,K:IZ2:,F,K:IZ1:,+,0,0,L3,INC,1.5)
** Set wup=t to account better for the high curvature of
the w resolute...
WUP=T
GROUP 7. Variables stored, solved & named
SOLVE(P1,V1,W1);SOLUTN(P1,Y,Y,Y,N,N,N)
SOLUTN(V1,P,P,P,P,P,N);SOLUTN(W1,P,P,P,P,P,N)
ONEPHS=F
SOLVE(V2,W2,R1,R2,H1,H2)
SOLUTN(V2,P,P,P,P,P,N);SOLUTN(W2,P,P,P,P,P,N)
SOLUTN(R1,P,P,P,P,P,N);SOLUTN(R2,P,P,P,P,P,N)
SOLUTN(H1,P,P,P,P,P,N);SOLUTN(H2,P,P,P,P,P,N)
STORE(MDOT)
GROUP 9. Properties of the medium (or media)
ENUL=WIN*DIAM/REYNO;ENUT=500*ENUL
RHO1=750;RHO2=36
PHINT(H1)=4E5;PHINT(H2)=2.5E6
GROUP 10. Inter-phase-transfer processes and properties
CINT(H1)=10;CINT(H2)=10;CMDOT=HEATBL;CFIPS=1E2
GROUP 11. Initialization of variable or porosity fields
FIINIT(P1)=1.E-10;FIINIT(W1)=WIN;FIINIT(W2)=WIN
REAL(R1IN,R2IN)
R1IN=0.99;R2IN=1-R1IN
FIINIT(R1)=R1IN;FIINIT(R2)=R2IN
FIINIT(H2)=PHINT(H2);FIINIT(H1)=PHINT(H1)
GROUP 13. Boundary conditions and special sources
Inlet velocities and volume fractions are the same for
both phases
INLET(INLET,LOW,1,1,1,NY,1,1,1,1)
VALUE(INLET,P1,R1IN*RHO1*WIN);VALUE(INLET,W1,WIN)
VALUE(INLET,H1,PHINT(H1));VALUE(INLET,P2,R2IN*RHO2*WIN)
VALUE(INLET,W2,WIN);VALUE(INLET,H2,PHINT(H2))

PATCH(OUTLET,HIGH,1,1,1,NY,NZ,NZ,1,1)
COVAL(OUTLET,P1,1.E3*RHO1,0.0);COVAL(OUTLET,P2,1.E3*RHO2,0.0)
COVAL(OUTLET,H1,ONLYMS,SAME);COVAL(OUTLET,H2,ONLYMS,SAME)

MESG(ACTIVATE HEAT TRANSFER?  (Y/N)
IF(:ANS:.EQ.Y) THEN
+  WALL(TOP,NORTH,1,1,NY,NY,1,NZ,1,1)
+  COVAL(TOP,H1,LOGLAW,4.5E5)

+  WALL(BOT,SOUTH,1,1,1,1,1,NZ,1,1)
+  COVAL(BOT,H1,LOGLAW,4.5E5)

+  PATCH(HEATER,NORTH,1,1,NY,NY,NZ1+(NZ2/2)+1,NZ1+NZ2,1,1)
+  COVAL(HEATER,H1,FIXFLU,1E5)
ELSE
+  SOLUTN(H1,Y,N,N,N,N,N)
+  SOLUTN(H2,Y,N,N,N,N,N)
ENDIF
GROUP 15. Termination of sweeps
LSWEEP=200;SELREF=T;RESFAC=0.1
GROUP 17. Under-relaxation devices
RELAX(P1,LINRLX,0.5)
REAL(DTF,FAC)
DTF=(L1/NZ1)/WIN
FAC=10
RELAX(V1,FALSDT,0.1*DTF);RELAX(W1,FALSDT,FAC*DTF)
RELAX(V2,FALSDT,0.1*DTF);RELAX(W2,FALSDT,FAC*DTF)
RELAX(H1,FALSDT,FAC*DTF);RELAX(H2,FALSDT,FAC*DTF)
RELAX(MDOT,LINRLX,0.5)
GROUP 22. Spot-value print-out
IYMON=5;IZMON=32
Activate graphical convergence monitoring
TSTSWP=-1
GROUP 23. Field print-out and plot control
photon use
p;;;

gr x 1
msg dense-phase volume-fraction contours
con r1 x 1 fi;0.1
msg press return for dense-phase ucrt
pause; con off; red
msg dense-phase ucrt
con vcrt x 1 fi;0.1
msg press return for dense-phase wcrt
pause; con off; red
msg dense-phase wcrt
con wcrt x 1 fi;0.1
msg press return for p1
pause; con off; red
msg pressure
con p1 x 1 fi;0.1
msg press return for dense-phase velocity vectors
pause; con off; red; gr off;gr ou x 1; red;  vec x 1 sh

enduse
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