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** Flow around cylinder ( 4 blocks).
**************************************************************
PHOTON USE
p ; ; ; ; ;

msg Computational Domain:
mgr 1 k 1 j 1 24 col 5
mgr 2 k 1 j 2 m  col 8
mgr 3 k 1 j 1 10 i 1 8 col 12
mgr 4 k 1 j 1 10 i 2 m col 14
pause
cl
set vec av off
msg Velocity Vectors:
vec k 1 sh
msg Press Any Key to Continue...
pause
cl
msg Contours of Uc1-component:
con uc1 k 1 fi;0.01
msg Press Any Key to Continue...
pause
cl
msg Contours of p1
con p1 k 1 fi;0.01
msg Press E  to exit PHOTON ...
ENDUSE
DISPLAY

This case concerns the prediction of laminar flow over a
half cylinder. The default Reynolds Number is 40.

The grid is composed of 4 blocks. Block 1 surrounding
the cylinder has a polar topology, and is 'unnaturally'
connected to the surrounding cartesian blocks.

The Q1 contains PHOTON commands.

ENDDIS
REAL(RC,RD,AM,PX,PY,PI6,XFF,XLL,YD,UIN,REYNO)
INTEGER(NI1,NI11,NI12,NI13,NJ1)
INTEGER(NI2,NI21,NI22,NI23,NJ2)
INTEGER(NI3,NJ3,NI4,NJ4)
** Problem definition:
NZ =1
PI6=3.1415/6.0
UIN = 1.0; REYNO = 40.0
MESG(Enter Reyolds Number in the range 0.1 - 2000 (40)
IF(REYNO.GT.2000) THEN
+ REYNO=2000
ELSE
+ IF(REYNO.LT..1) THEN
+   REYNO=0.1
+ ENDIF
ENDIF
TEXT(Flow around a Cylinder at Re = :REYNO:
TITLE
RC= 1.0; RD= 6*RC; XFF= -RD-4*RC; XLL= RD+12*RC; YD= RD+4*RC
RHO1=1.0; ENUL = 2*RC/REYNO
** 1st DOMAIN
NI11= 10; NI12=NI11*2; NI13=NI11
NI1=NI11+NI12+NI13; NJ1=24
**  2d DOMAIN
NI21 = 8; NI22=NI12; NI23=40; NI2= NI21+NI22+NI23
NJ2  = 8
** 3d DOMAIN
NI3 = NI21; NJ3  = NI11
** 4th DOMAIN
NI4 = NI23; NJ4  = NI13
GROUP 6. Body-fitted coordinates or grid distortion
BFC= T
AM = 1.0/SQRT(2.0)
** Make 1st block
GSET(P,P1,-RC,0.0,0.0); GSET(P,P2,RC,0.0,0.0)
GSET(P,P6,-RD,0.0,0.0); GSET(P,P3,RD,0.0,0.0)
GSET(P,P5,-RD*AM,RD*AM,0.0)
GSET(P,P4, RD*AM,RD*AM,0.0)
GSET(P,P7, XFF,0.0,0.0);  GSET(P, P8, XFF, YD,0.0)
GSET(P,P9, XLL,0.0,0.0);  GSET(P,P10, XLL, YD,0.0)
GSET(P,P11,-RD*AM,YD,0.0)
GSET(P,P12, RD*AM,YD,0.0)
GSET(P,P13,XFF,RD*AM,0.0)
GSET(P,P14,XLL,RD*AM,0.0)
GSET(L,L12,P1,P2,NI1 ,ARC,0.0,RC,0.0)
PX = RD*COS(PI6); PY = RD*SIN(PI6)
GSET(L,L34,P3,P4,NI13,ARC, PX,PY,0.0)
GSET(L,L45,P4,P5,NI12,ARC,0.0,RD,0.0)
GSET(L,L56,P5,P6,NI11,ARC,-PX,PY,0.0)
GSET(L,L23,P2,P3,NJ1 ,1.5)
GSET(L,L16,P1,P6,NJ1 ,1.5)
GSET(L,A35,P13,P5 ,NI21,1.0); GSET(L,A38,P13,P8 ,NJ2 ,1.0)
GSET(L,A44,P4 ,P14,NI23,1.0); GSET(L,A40,P14,P10,NJ2 ,1.0)
GSET(L,A81,P8 ,P11,NI21,1.0); GSET(L,A12,P11,P12,NI22,1.0)
GSET(L,A20,P12,P10,NI23,1.0)
GSET(L,L76,P7 ,P6 ,NI3 ,1.0); GSET(L,A73,P7 ,P13,NJ3 ,1.0)
GSET(L,L39,P3 ,P9 ,NI4 ,1.0); GSET(L,A94,P9 ,P14,NJ4 ,1.0)
GSET(D,NI1,NJ1+1,NZ,RC,RC,1.0)
GSET(F,F1,P1,-,P2,-,P3,P4.P5,P6,-)
GSET(M,F1,+I+J,1,1,1)
GSET(C,K:NZ+1:,F,K1,1,NX,1,NY,+,0.0,0.0,0.1,INC,1.0)
DUMPC(MBGR1)
** Make 2nd block
GSET(D,NI2,NJ2+1,NZ,RC,RC,1.0)
GSET(F,F2,P13,P5.P4,P14,-,P10,P12.P11,P8,-)
GSET(M,F2,+I+J,1,2,1)
GSET(C,K:NZ+1:,F,K1,1,NX,1,NY,+,0.0,0.0,0.1,INC,1.0)
DUMPC(MBGR2)
** Make 3rd block
GSET(D,NI3+1,NJ3+1,NZ,RC,RC,1.0)
GSET(F,F3,P7,-,P6,-,P5,-,P13,-)
GSET(M,F3,+I+J,1,1,1)
GSET(C,K:NZ+1:,F,K1,1,NX,1,NY,+,0.0,0.0,0.1,INC,1.0)
DUMPC(MBGR3)
** Make 4th block
GSET(D,NI4+1,NJ4+1,NZ,RC,RC,1.0)
GSET(F,F4,P3,-,P9,-,P14,-,P4,-)
GSET(M,F4,+I+J,2,1,1)
GSET(C,K:NZ+1:,F,K1,1,NX,1,NY,+,0.0,0.0,0.1,INC,1.0)
DUMPC(MBGR4)
** Assemble blocks:
MESG(Show grid? (N/y)
IF(:ANS:.EQ.Y) THEN
GCLEAR; GVIEW(Z); GGRID(Z,1,1,NI1+1,1,NJ1+1,4,0)
GGRID(Z,1,NI1+2,NI1+2+NI2,2,NJ2+2,6,0)
GGRID(Z,1,NI1+2+NI2+1,NI1+2+NI2+1+NI3,1,NJ3+1,9,0)
GGRID(Z,1,NI1+NI2+NI3+6,NI1+NI2+NI3+NI4+6,1,NJ4+1,13,0)
GDRAW
ENDIF
** North of 1 to South of 2
MPATCH(1,MBL1,NORTH,NI11+1,NI11+NI12,NJ1,NJ1,1,NZ,1,LSTEP)
MPATCH(2,MBL2,SOUTH,NI21+1,NI21+NI22,  2,  2,1,NZ,1,LSTEP)
** North of 3 to South of 2
MPATCH(3,MBL3 ,NORTH,1, NI3,NJ3,NJ3,1,NZ,1,LSTEP)
MPATCH(2,MBL2a,SOUTH,1,NI21,  2,  2,1,NZ,1,LSTEP)
** North of 4 to South of 2
MPATCH(4,MBL4 ,NORTH,          2,  NX,NJ4,NJ4,1,NZ,1,LSTEP)
MPATCH(2,MBL2b,SOUTH,NI21+NI22+1,  NX,  2,  2,1,NZ,1,LSTEP)
** East of 3 to North of 1
MPATCH(3,MBL3A,EAST ,NI3, NI3,  1,NJ3,1,NZ,1,LSTEP)
MPATCH(1,MBL1A,NORTH,  1,NI11,NJ1,NJ1,1,NZ,1,LSTEP)
** The next command sets the orientation of 1 relative to 3.
The default is NEH to SWL. Here:
N-S of 3 aligns with E-W of 1
E-W of 3 aligns with S-N of 1
H-L of 3 aligns with H-L of 1
SPEDAT sends last column ^ to show alignment
SPEDAT(SET,GCV,MBL1A,C,WNL)
** West of 4 to North of 1
MPATCH(4,MBL4A ,WEST ,          2,  2,  1,NJ4,1,NZ,1,LSTEP)
MPATCH(1,MBL1B,NORTH ,NI11+NI12+1, NX,NJ1,NJ1,1,NZ,1,LSTEP)
** The next command sets the orientation of 1 relative to 4.
The default is NEH to SWL. Here:
N-S of 4 aligns with W-E of 1
E-W of 4 aligns with N-S of 1
H-L of 4 aligns with H-L of 1
^
SPEDAT(SET,GCV,MBL1B,C,ESL)

GROUP 7. Variables stored, solved & named
SOLVE(U1,V1,P1)
STORE(PRPS)
GROUP 8. Terms in differential equations & devices
GROUP 13. Boundary conditions and special sources
** INLET
MPATCH(2,INL1,WEST,1,1,2,NY,1,NZ,1,LSTEP)
COVAL(INL1, P1,FIXFLU,RHO1*UIN)
COVAL(INL1,U1,ONLYMS,UIN);  COVAL(INL1,V1,ONLYMS,0.0)
MPATCH(3,INL2,WEST,1,1,1,NJ3,1,NZ,1,LSTEP)
COVAL(INL2,P1,FIXFLU,RHO1*UIN)
COVAL(INL2,U1,ONLYMS,UIN);  COVAL(INL2,V1,ONLYMS,0.0)
** WALL
MPATCH(1,WS,SWALL,1,NX,1,1,1,NZ,1,LSTEP)
COVAL(WS,U1,1.0,0.0);  COVAL(WS,V1,1.0,0.0)
** OUTLET
MPATCH(2,OUT1,NORTH,1,NI2,NY,NY,1,NZ,1,LSTEP)
COVAL(OUT1, P1,1.0E5,0.0)
MPATCH(2,OUT2,EAST,NX,NX,2,NY,1,NZ,1,LSTEP)
COVAL(OUT2, P1,1.0E5,0.0)
MPATCH(4,OUT3,EAST,NX,NX,1,NJ4,1,NZ,1,LSTEP)
COVAL(OUT3, P1,1.0E5,0.0)
GROUP 15. Termination of sweeps
LSWEEP= 350; TSTSWP= -1
FIINIT(U1) = 1.0
FIINIT(V1) = 0.0
GROUP 16. Termination of iterations
GROUP 17. Under-relaxation devices
GROUP 19. Data communicated by satellite to GROUND
GCV= T; LSG9=T
GROUP 21. Print-out of variables
GROUP 22. Spot-value print-out
IXMON= NI21/2+1; IYMON= NJ2/2+1; IZMON= 1
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