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PHOTON USE
p

use patgeo
MSG Velocity vectors
vec x 1 sh
msg
msg Press return to plot pressure contours
pause
cont p1 x 1 fil;.01
msg
msg Type e to End
ENDUSE

GROUP 1. Run title
TEXT(2D BODY-SECTION IN A WIND TUNNEL:   B531
TITLE
DISPLAY
This example demonstrates the flow around a 2-dimensional body
in close proximity to the wind-tunnel floor ,showing the effect
of the tunnel floor boundary layer on the pressure distribution.
A boundary layer is prescribed at the inlet.
ENDDIS
INTEGER(NZ1,NZ2,NZ3,NY1,NY2,NYP,NZTE)
REAL(COEF,WIN,WINB,PR,YY,KEIN,EPIN,TD,ENUTI)
NY1 denotes the number of cells under the body; NY2 is the
number above the body; one cell layer passes through the body.
NZ1 denotes the number of cells upstream of the body; NZ2
denotes the number spanning the body; and NZ3 denotes the
number down stream of the body. The total number of cells in
use is, therefore, (NY1+NY2+1)*(NZ1+NZ2+NZ3) .
NZ1=5;NZ2=15;NZ3=7;NY1=5;NY2=12
NZTE=NZ1+NZ2
** Coefficient in exit mass flow boundary condition.
COEF=1000.
GROUP 4. Y-direction grid specification
NY=NY1+NY2+1
GROUP 5. Z-direction grid specification
NZ=NZ1+NZ2+NZ3
GROUP 6. Body-fitted coordinates or grid distortion
GROUP 7. Variables stored, solved & named
SOLVE(P1,V1,W1);SOLUTN(P1,Y,Y,Y,N,N,N)
GROUP 9. Properties of the medium (or media)
RHO1=1.21;ENUL=1.49E-5
GROUP 11. Initialization of variable or porosity fields
WIN=62.
FIINIT(W1)=WIN
NYP=NY1+1
CONPOR(0.,CELL,1,NX,-NYP,-NYP,NZ1+1,NZTE)
GROUP 13. Boundary conditions and special sources
INLET(IN,LOW,1,NX,6,NY,1,1,1,1)
VALUE(IN,W1,WIN);VALUE(IN,P1,WIN*RHO1)
VALUE(IN,KE,KEIN);VALUE(IN,EP,EPIN)
PATCH(INB,LOW,1,NX,2,5,1,1,1,1)
COVAL(INB,KE,ONLYMS,KEIN)
COVAL(INB,EP,ONLYMS,EPIN)
** Tunnel floor boundary layer
PR=1./7.
INLET(B1,LOW,1,NX,1,1,1,1,1,1)
YY=1./12.
WINB=WIN*YY**PR
VALUE(B1,W1,WINB)
VALUE(B1,P1,WINB*RHO1)
INLET(B2,LOW,1,NX,2,2,1,1,1,1)
WINB=WIN*(2./6.-YY)**PR
VALUE(B2,W1,WINB)
VALUE(B2,P1,WINB*RHO1)
INLET(B3,LOW,1,NX,3,3,1,1,1,1)
WINB=WIN*(3./6.-YY)**PR
VALUE(B3,W1,WINB)
VALUE(B3,P1,WINB*RHO1)
INLET(B4,LOW,1,NX,4,4,1,1,1,1)
WINB=WIN*(4./6.-YY)**PR
VALUE(B4,W1,WINB)
VALUE(B4,P1,WINB*RHO1)
INLET(B5,LOW,1,NX,5,5,1,1,1,1)
WINB=WIN*(5./6.-YY)**PR
VALUE(B5,W1,WINB)
VALUE(B5,P1,WINB*RHO1)
WALL (WFUNFL,SOUTH,1,NX,1,1,1,NZ,1,1)
PATCH(OUT,HIGH,1,NX,1,NY,NZ,NZ,1,1)
COVAL(OUT,P1,COEF,0.)
GROUP 15. Termination of sweeps
LSWEEP=40
GROUP 16. Termination of iterations
LITER(P1)=10;LITER(V1)=1;LITER(W1)=1
GROUP 17. Under-relaxation devices
RELAX(P1,LINRLX,.5)
RELAX(V1,FALSDT,5.E-4)
RELAX(W1,FALSDT,5.E-4)
GROUP 19. Data communicated by satellite to GROUND
USEGRD=F
GROUP 22. Spot-value print-out
IXMON=1;IYMON=NY1;IZMON=NZTE+1
GROUP 23. Field print-out and plot control
NYPRIN=2;NZPRIN=2;TSTSWP=-1
SELREF=T; RESFAC=0.01
PATCH(UNDER,PROFIL,1,1,NY1,NY1,1,NZ,1,1)
PLOT(UNDER,P1,0.0,0.0)
PATCH(TOP,PROFIL,1,1,NY1+2,NY1+2,1,NZ,1,1)
PLOT(TOP,P1,0.0,0.0)
```