PHOTON USE p gr x 1 msg Grid vec x 1 sh MSG Velocity vectors msg Press return to redraw pause gr cl; gr ou x 1; red msg Press return to plot pressure contours pause cont p1 x 1 fil;.01 msg Type e to End ENDUSE GROUP 1. Run title TEXT(PLANE CHANNEL + SMOOTH EXPANSION.: B533 TITLE DISPLAY The problem considered is that defined by the International Association for Hydraulic Research Working Group on Refined Modelling of Flows for their 5th meeting. The report of the workshop is presented as a paper entitled 'Laminar flow in a complex geometry: a comparison', Int. j. numer. methods fluids, vol.5, 667-683(1985). The main features of the problem are: * laminar flow, Re=10.0 ( and 100.0); * the south boundary of the channel is given by the following analytical expression : y(z) = [tanh(2-30*z/Re)-tanh(2)]/2 for 0 < z< Re/3 * the north boundary is a symmetry plane located at y=1; * a parabolic profile for the axial velocity is specified at the inlet, w=3*(y-y*y/2) for z=0 and 0 < y< 1, v=0. ENDDIS Special variables introduced for this problem are:- RE........Value of the Reynolds number PRESSO....Outlet uniform relative pressure CT........Tanh(2) POWERZ....Power law in the Z direction POWERY....Power law in the Y direction REAL(RE,CT,A,B,VV,UU,ZZ,POWERZ,POWERY,C,DD,Y0,Y1,YY) RE=10.0;CT=0.9640275 GROUP 4. Y-direction grid specification NY=21;POWERY=1.3 GROUP 5. Z-direction grid specification NZ=21;POWERZ=1.5;ZWLAST=RE/3. GROUP 6. Body-fitted coordinates or grid distortion BFC=T; NONORT=T; SYMBFC=T **The next three YCs are kept at 0.0 to ensure that the w resolutes for iz=1 are parallel to the axis. This simplifies the specification of the inflow conditions, for the v resolute can be specified as zero. However, this does modify the geometry near the inlet. DO JJ=1,3 + A=JJ-1;ZZ=ZWLAST*(A/NZ)**POWERZ + SETPT(1,1,JJ,0.0,0.0,ZZ);SETPT(2,1,JJ,1.0,0.0,ZZ) ENDDO **For KK=4 on, the given analytical formula for the shape of the wall is employed DO JJ=4,22 + A=JJ-1; ZZ=ZWLAST*(A/NZ)**POWERZ; B=2-30*ZZ/RE + VV=2.7182818**B; UU=1.0/VV; DD=((VV-UU)/(VV+UU)-CT)/2. + SETPT(1,1,JJ,0.0,DD,ZZ) + SETPT(2,1,JJ,1.0,DD,ZZ) ENDDO ** Set high boundary grid DOMAIN(1,1,1,NY+1,NZ+1,NZ+1) SETLIN(YC,YF+(YL-YF)*LNJ**POWERY) ** Set low boundary grid DOMAIN(1,2,1,NY+1,1,1) SETLIN(YC,YF+(YL-YF)*LNJ**POWERY) ** Set north boundary grid DOMAIN(1,1,NY+1,NY+1,1,NZ+1) SETLIN(ZC,ZF+(ZL-ZF)*LNK**POWERZ) ** Apply algebraic interpolation over domain DOMAIN(1,2,1,NY+1,1,NZ+1);MAGIC(T) ** Apply Laplace solver for K greater than 2 to preserve shape of first two slabs for simple inlet conditions SLIDN=T;JMON=10;KMON=10;MSWP=50 DOMAIN(1,2,1,NY+1,3,NZ+1);MAGIC(L);VIEW(I,1) 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 DIFCUT=0.0 GROUP 9. Properties of the medium (or media) ENUL=0.1 GROUP 11. Initialization of variable or porosity fields FIINIT(W1)=.5 GROUP 13. Boundary conditions and special sources ** Inlet boundary conditions DO II=1,21 + Y0=((II-1)/NY)**POWERY; Y1=(II/NY)**POWERY + YY=(Y1+Y0)/2; C =3*(YY-YY**2/2) + INLET(INL:II:,LOW,1,1,II,II,1,1,1,1) + VALUE(INL:II:,P1,C*RHO1) + VALUE(INL:II:,W1,C) ENDDO ** Outlet boundary conditions PATCH(OUTLET,HIGH,1,1,1,NY,NZ,NZ,1,1);COVAL(OUTLET,P1,FIXP,0.071) COVAL(OUTLET,V1,ONLYMS,0.0);COVAL(OUTLET,W1,ONLYMS,0.0) ** Friction at the South wall WALL (SOUTH,SOUTH,1,1,1,1,1,NZ,1,1);COVAL(SOUTH,W1,1.0,0.0) GROUP 15. Termination of sweeps LSWEEP=100 GROUP 17. Under-relaxation devices RELAX(V1,FALSDT,1.0); RELAX(W1,FALSDT,1.0) GROUP 22. Spot-value print-out IZMON=10 GROUP 23. Field print-out and plot control ITABL=3;NPLT=2;NYPRIN=3;NZPRIN=3;TSTSWP=-1 SELREF=T; RESFAC=0.01 PATCH(INNER,PROFIL,1,1,1,1,1,NZ,1,1) PLOT(INNER,P1,0.0,0.0);PLOT(INNER,W1,0.0,0.0)