TALK=T;RUN(1,1)
DISPLAY An inviscid fluid flows steadily in a direction normal to a flat plate. Since the potential-flow equation which represents this situation is identical with that for flow through a highly resistive medium obeying Darcy's law, it is the latter problem which is solved, a device which is effected by the command DARCY=T. This entails that the pressure values computed correspond to 1.0E4 times the velocity potential. SELREF is set=f in order to prevent premature termination. The geometry of the problem is as follows: frictionless wall ----------------------------------------------------- --------> --------> ----> PLATE ----> | ^ ----> | ----> | | y| ---------------------------|------------------------- | frictionless wall z---> ENDDIS PHOTON USE p;;;;;; con p1 x 1 fi;0.001 msg contours of potential pause con w1 x 1 fi;0.001 msg contours of axial velocity pause con off;red vec x 1 sh msg velocity vectors ENDUSE GROUP 1. Run title and other preliminaries TEXT(Potential Flow over Perpendicular Plate TITLE GROUP 4 & 6 ny=20; yvlast=4.0; nz=40; zwlast=8.0 l(unigrid GROUP 7. Variables stored, solved & named SOLVE(P1,V1,W1); SOLUTN(P1,Y,Y,Y,N,N,N) GROUP 8. Terms (in differential equations) & devices TERMS(V1,Y,Y,N,P,P,P); TERMS(W1,Y,Y,N,P,P,P) GROUP 11. Initialization of variable or porosity fields FIINIT(P1)=0.0 GROUP 13. Boundary conditions and special sources **Upstream boundary PATCH(UPSTRM,LOW,1,1,1,NY,1,1,1,1) COVAL(UPSTRM,P1,FIXVAL,4.0) COVAL(UPSTRM,V1,ONLYMS,0.0); COVAL(UPSTRM,W1,ONLYMS,0.0) **Downstream boundary PATCH(DWNSTRM,HIGH,1,1,1,NY,NZ,NZ,1,1) COVAL(DWNSTRM,P1,FIXVAL,-4.0) COVAL(DWNSTRM,V1,ONLYMS,0.0); COVAL(DWNSTRM,W1,ONLYMS,0.0) **Plate PATCH(PLAT,HIGH,1,1,1,NY/2,NZ/2,NZ/2,1,1) COVAL(PLAT,W1,FIXVAL,0.0) **Distributed resistance DARCY=T GROUP 15. Termination of sweeps LSWEEP=30 GROUP 16. Termination of iterations LITER(P1)=-200 GROUP 21. Print-out of variables OUTPUT(P1,Y,Y,Y,Y,N,N); OUTPUT(V1,Y,Y,Y,Y,N,N) OUTPUT(W1,Y,Y,Y,Y,N,N) GROUP 22. Spot-value print-out IYMON=NY/2; IZMON=NZ/2; IPLTF=2 tstswp=-1 GROUP 23. Field print-out and plot control NYPRIN=NY/10; IZPRF=16; IZPRL=25 PATCH(PROF,PROFIL,1,1,1,NY,NZ/2,NZ/2,1,1) PLOT(PROF,W1,0.0,0.0) PATCH(CONT,CONTUR,1,1,1,NY,1,NZ,1,1); PLOT(CONT,P1,0.0,20.0) PLOT(CONT,W1,0.0,20.0); PLOT(CONT,V1,0.0,40.0) SELREF=F