GROUP 1. Run title and other preliminaries TEXT(Power-Law Fluid_2D FD Duct Flow TITLE The case considered is three-dimensional fully-developed, laminar flow of an incompressible power-law fluid in a rectangular duct of aspect ratio alfa=0.5, where alfa= height/width. The calculations are performed for a power-law Reynolds number Re of 100 and a fluid with a power-law index of 0.5. The solution exploits symmetry by performing the calculation over one quadrant of the duct cross section only. The flow Reynolds number is based on the hydraulic diameter of the duct. Data on the friction factor ( and hence pressure drop ) has been reported in 'Non-Newtonian Fluid Laminar Flow and Forced Convection Heat Transfer in Rectangular Ducts', S.X.Gao and J.P.Hartnett, Int.Comm. Heat Mass Transfer, Vol.19, p673, (1992). The data on the friction factor f is correlated by f*Re = 2.**(3*n+1)*(B+A/n)**n where n is the power-law index and A and B are constants which depend on the duct aspect ratio alfa. For the duct aspect ratio considered here A=0.244 and B=0.7276. For a Reynolds number of 100 and a power-law index of 0.5, the data indicates that f=0.0624 so that dp/dz=0.0935. The PHOENICS predictions yield values of f=0.061 and dp/dz=0.091, which are in very good agreement with the experimental values. REAL(HEIGHT,WIDTH,ALF,HD2,WD2,WIN,DPDZ,REY,FRIC) REAL(AIN,DHYD,FLOWIN) ** ALFA = HEIGHT/WIDTH WIDTH=2.0;ALF=0.5;HEIGHT=ALF*WIDTH HD2=0.5*HEIGHT;WD2=0.5*WIDTH WIN=1.0 REY=100.;DHYD=4.*WIDTH*HEIGHT/(2.*HEIGHT+2.*WIDTH) GROUP 3. X-direction grid specification AIN=HD2*WD2 XULAST=WD2;NX=20;GRDPWR(X,NX,XULAST,1.0) GROUP 4. Y-direction grid specification YVLAST=HD2;NY=20;GRDPWR(Y,NY,YVLAST,1.0) GROUP 7. Variables stored, solved & named SOLVE(P1,U1,V1,W1) GROUP 8. Terms (in differential equations) & devices TERMS(W1,N,P,P,P,P,P) GROUP 9. Properties of the medium (or media) ENUT=0.0 FLOWIN=RHO1*WIN*AIN REAL(POWER);POWER=0.5 ENULA=WIN**(2.0-POWER)*DHYD**POWER/REY ENULB=POWER ** enul = enula*(dwdy)*[0.5*(enulb-1)] ENUL=STRAIN;GENK=T;STORE(VISL) REAL(ACON,BCON);ACON=.244;BCON=.7276 FRIC=(2.**(3.*POWER+1.))*(BCON+ACON/POWER)**POWER/REY DPDZ=2.*FRIC*RHO1*WIN**2/DHYD FRIC DPDZ REY POWER GROUP 11. Initialization of variable or porosity fields FIINIT(W1)=WIN GROUP 12. Convection and diffusion adjustments PATCH(GP12CONH,CELL,1,NX,1,NY,1,NZ,1,1) COVAL(GP12CONH,U1,0.0,0.0);COVAL(GP12CONH,V1,0.0,0.0) COVAL(GP12CONH,W1,0.0,0.0) GROUP 13. Boundary conditions and special sources PATCH(WALLT,NWALL,1,NX,NY,NY,1,NZ,1,1) COVAL(WALLT,W1,1.0,0.0);COVAL(WALLT,U1,1.0,0.0) PATCH(WALLS,EWALL,NX,NX,1,NY,1,NZ,1,1) COVAL(WALLS,W1,1.0,0.0);COVAL(WALLS,V1,1.0,0.0) PATCH(RELIEF,CELL,NX/2,NX/2,NY/2,NY/2,1,NZ,1,1) COVAL(RELIEF,P1,FIXP,0.0) FDFSOL=T;USOURC=T PATCH(FDFW1DP,VOLUME,1,NX,1,NY,1,NZ,1,1) COVAL(FDFW1DP,W1,FLOWIN,GRND1) GROUP 15. Termination of sweeps LSWEEP=20;LITHYD=2;LITER(W1)=15 GROUP 16. Termination of iterations RESREF(P1)=1.E-12*WIN*AIN RESREF(W1)=1.E-12*DPDZ*ZWLAST*AIN RESREF(U1)=RESREF(W1);RESREF(V1)=RESREF(W1) GROUP 17. Under-relaxation devices REAL(DTF);DTF=50.*(YVLAST/NY)**2/ENULA RELAX(U1,FALSDT,DTF);RELAX(V1,FALSDT,DTF) RELAX(W1,FALSDT,DTF) GROUP 22. Spot-value print-out IXMON=NX-2;IYMON=NY-2;TSTSWP=-1 GROUP 23. Field print-out and plot control NPLT=1;NYPRIN=1;NZPRIN=1 GROUP 24. Dumps for restarts