PHOTON USE P gr ou x 1 set vec ref 1. vec x 1 sh msg( Water velocity distribution msg( Press ENTER to continue pause; vec off;red set vec comp - v2 w2 vec x 1 sh msg( Air velocity distribution msg( Press ENTER to continue pause; vec off;red con r2 x 1 1 z 1 19 fil;.0001 msg( Air volume fraction contours msg( Press E to finish ENDUSE GROUP 1. Run title and other preliminaries DISPLAY This problem is concerned with the prediction of lateral phase distribution for a bubbly flow in a duct. The phase distribution is caused by the interaction of gravity and lift forces. The latters are introduced by PLANT options. The interesting variants include the changing in gravity directions to see how the bubbles accumulate near the walls for the upflow situation, while they accumulate near the center of the duct for the down flow case. Note that some uderrelaxation adjustments could be used to accelerate the convergence. ENDDIS TEXT(PHASE DISTRIBUTION IN A DUCT:143 GROUP 4. Y-direction grid specification GRDPWR(Y,10,0.025,1.0) GROUP 5. Z-direction grid specification GRDPWR(Z,20,0.25,1.) GROUP 7. Variables stored, solved & named ONEPHS=F SOLVE(P1,V1,W1,V2,W2,R2,R1) GROUP 8. Terms (in differential equations) & devices TERMS(V1,Y,Y,Y,N,P,P);TERMS(V2,Y,Y,N,N,P,P) TERMS(W1,Y,Y,Y,N,P,P);TERMS(W2,Y,Y,N,N,P,P) GROUP 9. Properties of the medium (or media) ENUL=1.e-04;RHO1=1000.0;RHO2=1. GROUP 10. Inter-phase-transfer processes and properties ** Set a constant inter-phase friction coefficient CFIPS=100. GROUP 11. Initialization of variable or porosity fields FIINIT(W1)=0.5;FIINIT(W2)=0.5 FIINIT(R1)=0.9;FIINIT(R2)=0.1 GROUP 13. Boundary conditions and special sources PATCH(INLET,LOW,1,1,1,NY,1,1,1,1) COVAL(INLET,P1,FIXFLU,0.9*RHO1*0.5) COVAL(INLET,P2,FIXFLU,0.1*RHO2*0.5) COVAL(INLET,W1,ONLYMS,0.5) COVAL(INLET,W2,ONLYMS,0.5) **Wall friction boundary condition. PATCH(WALL,NWALL,1,1,NY,NY,1,NZ,1,1) COVAL(WALL,W1,1.0,0.) **Fixed static pressure exit boundary condition. PATCH(EXIT,HIGH,1,1,1,NY,NZ,NZ,1,1) COVAL(EXIT,P1,1.*RHO1,0.0) COVAL(EXIT,P2,1.*RHO2,0.0) ** Gravity PATCH(GRAVITY,PHASEM,1,NX,1,NY,1,NZ,1,LSTEP) COVAL(GRAVITY,W1,FIXFLU,-9.81) COVAL(GRAVITY,W2,FIXFLU,-9.81) PLANTBEGIN ** Lift force PATCH(LIFT,VOLUME,1,NX,1,NY,1,NZ,1,LSTEP)VAL=RG(1)*R2*(W2-W1)*(NORTH(W1)-W1)/DYG2D COVAL(LIFT,V1,FIXFLU,GRND) VAL=RG(1)*R2*(W1-W2)*(NORTH(W1)-W1)/DYG2D COVAL(LIFT,V2,FIXFLU,GRND) PLANTEND RG(3)=0.02;RG(1)=RG(3)*RHO1 GROUP 15. Termination of sweeps LSWEEP=200 GROUP 17. Under-relaxation devices RELAX(P1,LINRLX,0.5);RELAX(R1,LINRLX,0.5) RELAX(R2,LINRLX,0.5) RELAX(V1,FALSDT,.1);RELAX(W1,FALSDT,.1) RELAX(V2,FALSDT,.1);RELAX(W2,FALSDT,.1) GROUP 20. Preliminary print-out GROUP 22. Spot-value print-out IYMON=3;IZMON=10 GROUP 23. Field print-out and plot control NZPRIN=1;NYPRIN=1 NAMSAT=MOSG tstswp=-1 dmpstk=t DISTIL=T EX(P1)=1.108E+03; EX(V1)=5.782E-03; EX(V2)=5.586E-03 EX(W1)=4.913E-01; EX(W2)=5.943E-01; EX(R1)=9.144E-01 EX(R2)=8.557E-02 LIBREF=143 STOP