TALK=T;RUN( 1, 1) ** LOAD(x206) from the x Input Library GROUP 1. Run title and other preliminaries TEXT(LAM-BRE KE_1D DEVEL CHANNL FLOW :T206 TITLE DISPLAY The case considered is 2d fully-developed turbulent flow in a plane closed channel at a Re=1.E5. The turbulence is simulated by use of the Lam-Bremhorst low-Re k-e model. solution is obtained by use of the single-slab solver with a specified mass flow rate. A non-uniform grid is employed so as to concentrate cells very close to the wall. For this purpose a grid is generated which is a geometric progression with the property that the ratio of any two adjacent cell lengths is a constant. The calculation may also be performed with the low-Re Chen-kim k-e model, the Wilcox low-Re k-w models, the Menter k-w model, and k-w-SST model. No grid- dependency studies have been carried out. All models produce similar velocity and turbulence profiles, and the comparison between measured and computed friction factors f and velocity- defect parameters vdp are given below: f vdp Data 0.0156 2.32 Chen-Kim k-e 0.0163 2.18 Lam Bremhorst k-e 0.0177 2.16 Wilcox 1988 k-w model 0.0163 2.08 Wilcox 2088 k-w model 0.0155 2.14 Menter k-w model 0.0162 2.04 k-w SST model 0.0152 2.11 where f=8.*(wstar/wbulk)**2 and and vdp=(wcl-wbulk)/wstar. ENDDIS The following AUTOPLOT use file produces three plots; the first is the axial velocity profile; the second is the turbulence energy profile; and the third is the eddy-viscosity profile. AUTOPLOT USE file phi 5 da 1 w1;col9 1 msg Velocity (W1) profile msg Press RETURN to continue pause clear da 1 ke;col9 1 msg KE profile msg Press RETURN to continue pause clear da 1 ENUT;col9 1 msg Press e to END ENDUSE CHAR(CTURB,TLSC);BOOLEAN(VARLAM);VARLAM=T REAL(HGHT,WIN,REY,REYH,DHYDR,MIXL,FRIC,DPDZ,MASIN,DTF) REAL(TKEIN,EPSIN,DELT1,DELT2,DELT3,US,EPSPLS) REAL(KFAC,DELY,GR,GYPLUS,GWPLUS,GWR);INTEGER(JJM,JJM1) ** NB: The the hydraulic diameter is equal to 2.*duct height, so that pipe-flow correlations still apply with diameter replaced by 2.*height HGHT=0.1;WIN=1.0; REY=1.E5;DHYDR=2.*HGHT; REYH=2.*REY FRIC=1./(1.82*LOG10(REYH)-1.64)**2 US=WIN*(FRIC/8.)**0.5;DPDZ=0.5*RHO1*WIN*WIN*FRIC/DHYDR ** estimate initial values from K+=2 & EP+=1./(ak*Y+) EPSPLS=1./(0.41*100.) TKEIN=2.*US*US;ENULA=WIN*HGHT/REY;EPSIN=EPSPLS*US**4/ENULA GROUP 4. Y-direction grid specification ENULA=WIN*HGHT/REY ** define first dely from wall and the grid-expansion factor Kfac which defines a constant ratio of lengths of two adjacent cells. DELT1=1.*ENULA/US;KFAC=1.1;DELY=DELT1/(0.5*HGHT) ** calculate NY from dely & Kfac REAL(AA) AA=(YVLAST/DELY)*(KFAC-1.0)+1.0;AA=LOG(AA)/LOG(KFAC)+1.0001 NY=AA ** define uniform grid initially IREGY=1;GRDPWR(Y,NY,YVLAST,1.0) ** compute expanding grid from north boundary YFRAC(NY)=1.0 DO JJ=NY,2,-1 + JJM=JJ-1 + YFRAC(JJM)=YFRAC(JJ)-DELY + DELY=KFAC*DELY ENDDO YVLAST=0.5*HGHT GROUP 5. Z-direction grid specification ZWLAST=0.1*HGHT GROUP 7. Variables stored, solved & named SOLVE(W1);STORE(ENUT,LEN1);SOLUTN(W1,P,P,P,P,P,N) MESG( Enter the required turbulence model: MESG( CK - Chen-Kim low-Re k-e model MESG( LB - Lam-Bemhorst low-Re k-e model (default) MESG( KW - Wilcox 1988 low-re k-omega model MESG( KWR - Wilcox 2008 low-re k-omega model MESG( KWM - Menter 1992 k-w model MESG( KWS - k-w SST model MESG( READVDU(CTURB,CHAR,LB) CASE :CTURB: OF WHEN CK,2 + TEXT(CHEN-KIM KE_1D DEVEL CHANNL FLOW :T206 + MESG(Chen-Kim low-Re k-e model + TURMOD(KECHEN-LOWRE);STORE(REYN);TLSC=EP WHEN LB,2 + MESG(Lam-Bremhorst low-Re k-e model + TURMOD(KEMODL-LOWRE);STORE(REYN);TLSC=EP WHEN KW,2 + TEXT(Wilcox 1988 k w_1D DEVEL CHANNL FLOW :T206 + MESG(Wilcox 1988 k-w low-Re model + TURMOD(KWMODL-LOWRE);TLSC=OMEG + EPSIN=EPSIN/(0.09*TKEIN) WHEN KWR,3 + TEXT(Wilcox 2008 k w_1D DEVEL CHANNL FLOW :T206 + MESG(Wilcox 2008 k-w low-Re model + TURMOD(KWMODLR-LOWRE);TLSC=OMEG + EPSIN=EPSIN/(0.09*TKEIN);FIINIT(FBP)=1.0 WHEN KWM,3 + TEXT(MENTER K-W DEVELOPED CHANNEL FLOW:T206 + MESG(Menter 1992 k-w low-Re model + TURMOD(KWMENTER-LOWRE);TLSC=OMEG + EPSIN=EPSIN/(0.09*TKEIN) + STORE(DKDY,DFDY,CDWS,SIGK,SIGW) WHEN KWS,3 TEXT(SST K-W DEVELOPED CHANNEL FLOW:T206 + MESG(Menter 1992 k-w SST low-Re model + TURMOD(KWSST-LOWRE);TLSC=OMEG + EPSIN=EPSIN/(0.09*TKEIN) + STORE(DKDY,DFDY,CDWS,SIGK,SIGW) ENDCASE GROUP 8. Terms (in differential equations) & devices ** Deactivate convection TERMS(W1,N,N,P,P,P,P);TERMS(KE,Y,N,P,P,P,P) TERMS(:TLSC:,Y,N,P,P,P,P) GROUP 9. Properties of the medium (or media) ENUL=ENULA ** test for ground-set enul IF(VARLAM) THEN + TMP1=CONST;TMP1A=0.0;ENUL=LINTEM ENDIF GROUP 11. Initialization of variable or porosity fields FIINIT(:TLSC:)=EPSIN;FIINIT(KE)=TKEIN ** use log-law for initial W profile DO JJ=1,NY +PATCH(IN:JJ:,INIVAL,1,NX,JJ,JJ,1,NZ,1,1) +GR=0.5*YFRAC(JJ) IF(JJ.NE.1) THEN + JJM1=JJ-1 + GR=YFRAC(JJM1)+0.5*(YFRAC(JJ)-YFRAC(JJM1)) ENDIF +GYPLUS=YVLAST*(1.-GR)*US/ENULA +GWPLUS=LOG(GYPLUS)/0.41+5.25 IF(GYPLUS.LE.11.5) THEN + GWPLUS=GYPLUS ENDIF +INIT(IN:JJ:,W1,ZERO,GWPLUS*US) ENDDO GROUP 13. Boundary conditions and special sources WALLCO=GRND2 WALL(WALLN,NORTH,1,1,NY,NY,1,NZ,1,1);COVAL(WALLN,W1,LOGLAW,0.0) MASIN=RHO1*WIN*0.5*HGHT ** Activate single-slab solver with specified mass flow rate FDSOLV(FLOW,MASIN) GROUP 15. Termination of sweeps LSWEEP=30;LITHYD=10 GROUP 16. Termination of iterations GROUP 17. Under-relaxation devices DTF=5.0*ZWLAST/WIN; RELAX(W1,FALSDT,DTF) IF(:TLSC:.EQ.OMEG) THEN + DTF=DTF*10.; RELAX(KE,FALSDT,DTF); RELAX(:TLSC:,FALSDT,DTF) ELSE + KELIN=3; RELAX(KE,LINRLX,0.6); RELAX(EP,LINRLX,1.0) ENDIF GROUP 18. Limits on variables or increments to them VARMIN(W1)=1.E-10 GROUP 22. Spot-value print-out ITABL=3;IYMON=NY-2;NZPRIN=1;NYPRIN=2;IYPRF=1;NUMCLS=5 TSTSWP=-1 GROUP 24. Dumps for restarts IF(IENUTA.LE.11) THEN + STORE(FMU,REYT,FONE,FTWO) ENDIF STORE(STRS,YPLS,SKIN) (stored of FRIC is 8.*STRS/(:WIN:*:WIN:)) (stored of UTAU is STRS^0.5) (stored of VDP is (W1[&1&]-WIN)/UTAU[&NY&]) (make ffac is 0.0) (make ustar is 0.0) (make vdus is 0.0) (store1 of ffac at walln is fric) (store1 of ustar at walln is utau) (store1 of vdus at walln is vdp) ** print to inforout file (print of f is ffac) (print of u* is ustar) (print of (ucl-ub)/u* is vdus) distil=t CASE :CTURB: OF WHEN CK,2 +EX(W1 )=7.491E-01;EX(KE )=5.482E-03 +EX(EP )=1.735E-01;EX(VDP )=2.178E+00 +EX(UTAU)=8.024E-04;EX(FRIC)=2.864E-04 +EX(SKIN)=6.703E-02;EX(YPLS)=8.975E-03 +EX(STRS)=3.580E-05;EX(FTWO)=9.570E-01 +EX(FONE)=2.824E+00;EX(REYT)=9.896E+02 +EX(FMU )=7.315E-01;EX(EPKE)=6.976E+07 +EX(REYN)=5.583E+02;EX(LTLS)=3.426E-04 +EX(WDIS)=9.268E-03;EX(LEN1)=2.593E-03 +EX(ENUT)=8.609E-05 WHEN LB,2 +EX(W1 )=7.528E-01;EX(KE )=6.019E-03 +EX(EP )=1.933E-01;EX(VDP )=2.163E+00 +EX(UTAU)=8.367E-04;EX(FRIC)=3.118E-04 +EX(SKIN)=6.158E-02;EX(YPLS)=9.364E-03 +EX(STRS)=3.897E-05;EX(FTWO)=9.576E-01 +EX(FONE)=2.369E+00;EX(REYT)=1.039E+03 +EX(FMU )=7.372E-01;EX(EPKE)=8.555E+07 +EX(REYN)=5.732E+02;EX(LTLS)=3.426E-04 +EX(WDIS)=9.268E-03;EX(LEN1)=2.616E-03 +EX(ENUT)=9.020E-05 WHEN KW,2 +EX(W1 )=7.417E-01;EX(KE )=5.438E-03 +EX(EP )=4.047E-01;EX(SKIN)=6.731E-02 +EX(YPLS)=8.957E-03;EX(STRS)=3.565E-05 +EX(FTWO)=8.509E-01;EX(FONE)=1.346E+00 +EX(REYT)=9.210E+01;EX(FMU )=7.602E-01 +EX(OMEG)=1.406E+04;EX(LEN1)=2.790E-03 +EX(ENUT)=8.769E-05;EX(VDP )=2.077E+00 +EX(UTAU)=8.007E-04;EX(FRIC)=2.852E-04 WHEN KWR,3 +EX(W1 )=7.405E-01;EX(KE )=4.227E-03 +EX(EP )=1.808E-01;EX(VDP )=2.141E+00 +EX(UTAU)=7.824E-04;EX(FRIC)=2.721E-04 +EX(SKIN)=7.055E-02;EX(YPLS)=8.749E-03 +EX(STRS)=3.402E-05;EX(DWDY)=3.144E+02 +EX(GEN1)=4.287E+05;EX(FBP )=1.000E+00 +EX(OMEG)=1.499E+04;EX(LEN1)=2.620E-03 +EX(ENUT)=8.327E-05 WHEN KWM,3 +EX(W1 )=7.441E-01;EX(VDP )=2.031E+00 +EX(UTAU)=8.049E-04;EX(FRIC)=2.882E-04 +EX(SKIN)=6.661E-02;EX(YPLS)=9.004E-03 +EX(STRS)=3.603E-05;EX(DFDY)=6.437E+08 +EX(BF1 )=9.986E-01;EX(LTLS)=3.426E-04 +EX(WDIS)=9.268E-03;EX(OMEG)=1.407E+04 +EX(LEN1)=2.767E-03;EX(ENUT)=9.029E-05 +EX(KE )=4.453E-03;EX(EP )=1.942E-01 +EX(SIGW)=1.998E+00;EX(SIGK)=1.997E+00 +EX(CDWS)=9.188E-03;EX(DKDY)=2.548E+00 WHEN KWS,3 +EX(W1 )=7.415E-01;EX(KE )=4.187E-03 +EX(EP )=1.770E-01;EX(VDP )=2.107E+00 +EX(UTAU)=7.743E-04;EX(FRIC)=2.665E-04 +EX(SKIN)=7.203E-02;EX(YPLS)=8.658E-03 +EX(STRS)=3.332E-05;EX(SIGW)=1.998E+00 +EX(SIGK)=1.998E+00;EX(CDWS)=1.285E-02 +EX(DFDY)=6.418E+08;EX(DKDY)=2.351E+00 +EX(LTLS)=3.426E-04;EX(WDIS)=9.268E-03 +EX(GEN1)=4.179E+05;EX(BF2 )=1.000E+00 +EX(BF1 )=9.977E-01;EX(OMEG)=1.418E+04 +EX(LEN1)=2.711E-03;EX(ENUT)=8.368E-05 ENDCASE LIBREF = 206 STOP