GROUP 1. Run title and other preliminaries TEXT(2S K-E MODEL_1D DEVELOPED PIPE FLOW:T401 TITLE DISPLAY The case considered is fully-developed turbulent flow in a circular pipe at a Reynolds number of 1.E5. Calculations are made with both the standard 2-scale k-e turbulence model. For this case, both models produce very similar results. ENDDIS CHAR(CTURB) MESG( Enter the required turbulence model: MESG( KE - Standard k-e model MESG( TSKE - 2-scale k-e model (default) MESG( READVDU(CTURB,CHAR,TSKE) REAL(DELT,US);BOOLEAN(TSKE) REAL(DIAM,WIN,REY,TKEIN,EPSIN,MIXL,FRIC,DPDZ,MASIN,DTF) DIAM=0.1;WIN=1.0; REY=1.E5;FRIC=1./(1.82*LOG10(REY)-1.64)**2 DPDZ=FRIC*RHO1*WIN*WIN/(2.*DIAM);US=WIN*(FRIC/8.)**0.5 US TKEIN=0.25*WIN*WIN*FRIC MIXL=0.09*0.5*DIAM;EPSIN=TKEIN**1.5/MIXL*0.1643 GROUP 3. X-direction grid specification CARTES=F;XULAST=0.1 GROUP 4. Y-direction grid specification ENUL=WIN*DIAM/REY;DELT=2.*40.*ENUL/US NREGY=2; REGEXT(Y,0.5*DIAM) IREGY=1;GRDPWR(Y,29,0.5*DIAM-DELT,0.8) IREGY=2;GRDPWR(Y,1,DELT,1.0) GROUP 5. Z-direction grid specification ZWLAST=0.1*DIAM GROUP 7. Variables stored, solved & named SOLVE(W1);STORE(ENUT,LEN1,GENK) CASE :CTURB: OF WHEN TSKE,4 + MESG(2-scale k-e turbulence model ** also store kt/kp & et/ep + TURMOD(TSKEMO);STORE(KTKP,ETEP);TSKE=T WHEN KE,2 + MESG(Standard k-e turbulence model + TURMOD(KEMODL);KELIN=1;TSKE=F ENDCASE GROUP 8. Terms (in differential equations) & devices ** deactivate convection terms TERMS(W1,N,N,P,P,P,P);TERMS(EP,Y,N,P,P,P,P) IF(TSKE) THEN + TERMS(KP,Y,N,P,P,P,P) + TERMS(KT,Y,N,P,P,P,P);TERMS(ET,Y,N,P,P,P,P) ELSE + TERMS(KE,Y,N,P,P,P,P) ENDIF GROUP 11. Initialization of variable or porosity fields FIINIT(W1)=WIN;FIINIT(EP)=EPSIN;FIINIT(KE)=TKEIN IF(TSKE) THEN + REAL(KTDKP);KTDKP=0.25 + FIINIT(ET)=EPSIN;FIINIT(KP)=TKEIN/(1.+KTDKP) + FIINIT(KT)=KTDKP*FIINIT(KP) ENDIF GROUP 13. Boundary conditions and special sources WALL(WALLN,NORTH,1,1,NY,NY,1,NZ,1,1) PATCH(PFORW,VOLUME,1,1,1,NY,1,NZ,1,1) COVAL(PFORW,W1,FIXFLU,DPDZ) GROUP 15. Termination of sweeps LSWEEP=50;TSTSWP=-1;LITHYD=10 GROUP 16. Termination of iterations MASIN=RHO1*WIN*DIAM*DIAM/80. GROUP 17. Under-relaxation devices DTF=15.*ZWLAST/WIN;VARMIN(W1)=1.E-10;WALPRN=T GROUP 22. Spot-value print-out IYMON=NY-2;ITABL=3;NPLT=2;NZPRIN=1;NYPRIN=1;IYPRF=1 GROUP 24. Dumps for restarts RELAX(W1,FALSDT,DTF); RELAX(EP,FALSDT,DTF) IF(TSKE) THEN + RESFAC=1.E-4; RELAX(KP,FALSDT,DTF); RELAX(EP,FALSDT,DTF) + RELAX(KT,FALSDT,DTF); RELAX(ET,FALSDT,DTF) ELSE + RELAX(KE,FALSDT,DTF) ENDIF