PHOTON USE
  p
  phi
  1 1 1
 
  msg         Potential flow over a double-wedge airfoil
  msg
  set ref vec 10
  msg   velocity vectors:
  gr ou x 1;vec x 1 sh
  msg
  msg Press  to continue
  pause
  vec off;red
  msg        Axial velocity contours:
  con w1 x 1 fi;.01
  msg
  msg Press  to continue
  pause
  con off;red
  msg        Contours of velocity potential:
  con pot x 1 fi;.01
  msg
  msg Press e to END
  enduse
  
    GROUP 1. Run title and other preliminaries
TEXT(Flow Over Double-Wedge Airfoil    
TITLE
  DISPLAY
     An inviscid fluid flows steadily past a double-wedge
  airfoil. The problem is solved in the same manner as in case
  115. The velocity components are computed by activation
  (through POTVEL) of a sequence in GREX3.
     The geometry of the problem is sketched below.
 
                       frictionless wall
     ____________________________________________________
 
                           ----------->
     ---->                                        ---->
 
                               _-_
     ---->                  __|***|__             ---->
   ^                     __|*********|__
  y|                  __|***************|__
   | ________________|*********************|______________
                       frictionless wall
                             z---->
  ENDDIS
    
    GROUP 4. Y-direction grid specification
GRDPWR(Y,20,1.0,1.0)
 
    GROUP 5. Z-direction grid specification
GRDPWR(Z,40,8.0,1.0)
 
    GROUP 7. Variables stored, solved & named
SOLVE(POT)
STORE(V1,W1,HPOR,VPOR,NPOR)
    
    GROUP 11. Initialization of variable or porosity fields
     The wedge is constructed by setting the high-area porosities
     to 0.0 for appropriate cells.

DO II=1,5
+ PATCH(HPOR:II:,INIVAL,1,1,:II:,:II:,:10+2*II:,:30-2*II:,1,1)
+ INIT(HPOR:II:,HPOR,0.0,0.0)
+ INIT(HPOR:II:,VPOR,0.0,0.0)
+ INIT(HPOR:II:,NPOR,0.0,0.0)
ENDDO
 
    GROUP 13. Boundary conditions and special sources
   **Upstream boundary
PATCH(UPSTRM,LOW,1,1,1,NY,1,1,1,1)
COVAL(UPSTRM,POT,FIXVAL,4.0)
   **Downstream boundary
PATCH(DWNSTRM,HIGH,1,1,1,NY,NZ,NZ,1,1)
COVAL(DWNSTRM,POT,FIXVAL,-4.0)
 
    GROUP 15. Termination of sweeps
LSWEEP=2
 
    GROUP 16. Termination of iterations
LITER(POT)=-20;OVRRLX=1.4
    GROUP 19. Data communicated by satellite to GROUND
POTVEL=T
    GROUP 21. Print-out of variables
OUTPUT(POT,Y,Y,Y,Y,N,N);OUTPUT(HPOR,Y,N,N,N,N,N)
OUTPUT(W1,Y,N,N,N,N,N);OUTPUT(V1,Y,N,N,N,N,N)
    GROUP 22. Spot-value print-out
IYMON=NY/4+1;IZMON=NZ/2;IPLTF=2
    GROUP 23. Field print-out and plot control
IZPRF=16;IZPRL=25;NYPRIN=1;IYPRL=NY/2
PATCH(CONT,CONTUR,1,1,1,NY,1,NZ,1,1)
PLOT(CONT,POT,0.0,40.0)
PLOT(CONT,V1,0.0,10.0);PLOT(CONT,W1,0.0,10.0)
    GROUP 24. Dumps for restarts