TEXT(RSTM_1DY DEVELOPED CHANNEL FLOW :T600 TITLE DISPLAY The problem considered is 1dy fully-developed turbulent flow in a channel at a Reynolds number of 5.E4 with heat and mass transfer. The turbulence is simulated by use of the Reynolds stress transport model (RSTM), and optionally by use of the k-e model. For heat and scalar transport with the RSTM, one of the following models may be employed: a simple gradient-diffusion model (IRSMSM=0); a generalised gradient-diffusion model (IRSMSM=1); or a full transport model (IRSMSM=2). The laminar Prandtl number is 3.0, and the energy equation may be solved via H1 or TEM1. ENDDIS For fully-smooth conditions channel-flow data indicates that the friction factor f = 0.018 and the Nusselt number Nu =392. The Petukhov correlation ( see below ) is used to estimate the Nusselt number. The PHOENICS predictions yield the following results: k-eps model f = 0.018 Nu = 401 RSTM gradient-diffusion model f = 0.018 Nu = 391 RSTM generalised-diffusion model f = 0.018 Nu = 412 RSTM full transport model f = 0.018 Nu = 409. These values agree closely with the data. The PIL variable WALPRN has been set to T, thereby activating printout of the local friction factor (sloc) and Stanton number (Stloc) in the RESULT file. In order to convert these values to f and Nu above, the following relations should be used: f = 8.*sloc*(W1(NY)/WIN)**2 Nu = REYH*PRNDTL(H1)*Stloc*W1(NY)*(TW-TEM1(NY))/[WIN*(TW-TB)] where TB is the bulk temperature printed in the RESULT file. The expected values are: sloc=4.923E-3 and Stloc=2.512E-3. BOOLEAN(KEMOD,HEAT);CHAR(CH1); REAL(DHYDR,DELT,US,REYH) REAL(HGHT,WIN,REY,TKEIN,EPSIN,MIXL,FRIC,DPDZ,MASIN,DTF) ** CH1=H1 activates solution of the energy eqn via H1 =TEM1 '' '' '' '' '' '' '' TEM1 CH1=TEM1 ** KEMOD =T selects k-eps solution ** HEAT =T activates heat/scalar transport ** IRSMSM=0 simple-gradient model for heat/scalar transport =1 generalised-gradient model =2 flux transport model KEMOD=F;HEAT=T;IRSMSM=2 ** 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=1.0;WIN=1.0; REY=5.E4;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 REY FRIC US DPDZ TKEIN=0.25*WIN*WIN*FRIC MIXL=0.09*0.5*HGHT;EPSIN=0.1643*TKEIN**1.5/MIXL ENUL=WIN*HGHT/REY;DELT=2.*40.*ENUL/US;NREGY=2; REGEXT(Y,0.5*HGHT) IREGY=1;GRDPWR(Y,29,0.5*HGHT-DELT,0.8);IREGY=2;GRDPWR(Y,1,DELT,1.0) SOLVE(W1) IF(HEAT) THEN + SOLVE(:CH1:);SOLVE(SC1,SC2) ENDIF ** prescribed pressure-force for w1-equation PATCH(PFOR,VOLUME,1,1,1,NY,1,NZ,1,1);COVAL(PFOR,W1,FIXFLU,DPDZ) IF(KEMOD) THEN + TURMOD(KEMODL);STORE(ENUT,LEN1);IRSMSM=0 + PATCH(WAL1,NWALL,1,1,NY,NY,1,NZ,1,1) + COVAL(WAL1,W1,LOGLAW,0.0);COVAL(WAL1,EP,LOGLAW,LOGLAW) ELSE + PATCH(WAL1,NWALL,1,1,NY,NY,1,NZ,1,1);COVAL(WAL1,W1,1.0,0.0) + STORE(V1,KE,DWDY,PVW,PW2,PV2,PU2,DVW) + STORE(PK,EPDK,FWAL,VWDK,U2DK,V2DK,W2DK) + DTF=0.02;TURMOD(REYSTRS,DTF,WAL1) + PATCH(SMPLS,SOUTH,1,1,1,1,1,NZ,1,1);COVAL(SMPLS,VWRS,GRND1,0.0) ENDIF ** deactivate convection for single-slab solution TERMS(W1,P,N,P,P,P,P);TERMS(EP,P,N,P,P,P,P) IF(KEMOD) THEN + COVAL(WAL1,KE,LOGLAW,LOGLAW);TERMS(KE,P,N,P,P,P,P) ELSE + TERMS(U2RS,P,N,P,P,P,P);TERMS(V2RS,P,N,P,P,P,P) + TERMS(W2RS,P,N,P,P,P,P);TERMS(VWRS,P,N,P,P,P,P) ENDIF FIINIT(W1)=WIN;FIINIT(V1)=0.0;FIINIT(KE)=TKEIN;FIINIT(EP)=EPSIN REAL(FLOW);FLOW=RHO1*WIN*HGHT RESREF(W1)=1.E-12*FLOW*WIN; RESREF(EP)=1.E-12*FLOW*EPSIN IF(KEMOD) THEN + RELAX(W1,FALSDT,1.E2) + RELAX(EP,FALSDT,10.0); RELAX(KE,FALSDT,10.0) + RESREF(KE)=1.E-12*FLOW*TKEIN ELSE + FIINIT(W2RS)=2.*FIINIT(KE)/3.;FIINIT(V2RS)=2.*FIINIT(KE)/3. + FIINIT(U2RS)=2.*FIINIT(KE)/3.;FIINIT(VWRS)=0.3*FIINIT(KE) + RELAX(W1,FALSDT,0.3) + RESREF(U2RS)=1.E-12*FLOW*FIINIT(U2RS) + RESREF(V2RS)=1.E-12*FLOW*FIINIT(V2RS) + RESREF(W2RS)=1.E-12*FLOW*FIINIT(W2RS) + RESREF(VWRS)=1.E-12*FLOW*FIINIT(VWRS) ENDIF IF(KEMOD) THEN + LSWEEP=15;NPLT=5;LITHYD=10 ELSE + LSWEEP=160;LITHYD=8;NPLT=20 + OUTPUT(PU2,N,N,N,N,N,N);OUTPUT(PV2,N,N,N,N,N,N) ENDIF OUTPUT(V1,N,N,N,N,N,N);NYPRIN=1;IYMON=NY-1;TSTSWP=-1 YPLS=T;WALPRN=T ** prescribe energy flow from slab and fluid specific heat estimated from Dittus-Boelter Nu=0.023*Re**0.8*Pr**0.4 with (Tw-Tb)=5.0 IF(HEAT) THEN + REAL(NUSS,COND,CP,QIN,DTDZ,AWAL,TW,XR,DTSC,HW,DSDZ) + PRNDTL(H1)=3.0;TW=10. + PRNDTL(SC1)=PRNDTL(H1);PRNDTL(SC2)=PRNDTL(H1) + NUSS=0.023*REYH**0.8*PRNDTL(H1)**0.4 + CP=3.0;COND=RHO1*CP*ENUL/PRNDTL(H1) + CP1=CP ** AWAL is wall surface area per unit length + AWAL=0.5*HGHT*XULAST;QIN=NUSS*5.0*COND/DHYDR + NUSS + QIN + DSDZ=QIN*AWAL/(CP*FLOW);DTDZ=CP*DSDZ IF(:CH1:.EQ.H1) THEN + TMP1A=0.0;TMP1B=1./CP;TMP1=LINH;HW=CP*TW + STORE(TEMP);OUTPUT(TEMP,Y,Y,Y,Y,Y,Y) ENDIF IF(:CH1:.EQ.TEM1) THEN + HW=TW ENDIF + AWAL + TERMS(:CH1:,N,N,P,P,P,P) + TERMS(SC1,N,N,P,P,P,P);TERMS(SC2,N,N,P,P,P,P) + FIINIT(:CH1:)=0.5*HW;FIINIT(SC1)=0.5*TW + COVAL(WAL1,:CH1:,LOGLAW,HW);COVAL(WAL1,SC1,LOGLAW,TW) + COVAL(WAL1,SC2,LOGLAW,TW) ** temperature source/sink term for fully-developed flow + PATCH(FDFCWT,PHASEM,1,NX,1,NY,1,NZ,1,1) + COVAL(FDFCWT,:CH1:,DTDZ,HW);COVAL(FDFCWT,SC1,DSDZ,TW) + COVAL(FDFCWT,SC2,DSDZ,TW);DTSC=20. + FDFSOL=T; RESREF(:CH1:)=1.E-12*QIN*AWAL*ZWLAST + RESREF(SC1)=RESREF(:CH1:); RESREF(SC2)=RESREF(SC1) ** compute expected Nusselt number from Petukhov correlation and printout from satellite + XR=1.07+12.7*(PRNDTL(H1)**.666-1.)*(FRIC/8.)**0.5 + NUSS=REYH*PRNDTL(H1)*FRIC/(8.*XR) + NUSS + COND + DHYDR IF(IRSMSM.EQ.1) THEN + DTSC=1.0;STORE(DSDY) + RELAX(VTRS,LINRLX,0.2); RELAX(VSC1,LINRLX,0.2) + RELAX(VSC2,LINRLX,0.2) + OUTPUT(VTRS,Y,Y,Y,Y,Y,Y);FIINIT(:CH1:)=0.9*HW + FIINIT(SC1)=0.9*TW ENDIF IF(IRSMSM.EQ.2) THEN + TERMS(VTRS,N,N,P,P,P,P);TERMS(VSC1,N,N,P,P,P,P) + TERMS(VSC2,N,N,P,P,P,P);STORE(DSDY) + COVAL(SMPLS,VTRS,GRND1,0.0);DTSC=10. + COVAL(SMPLS,VSC1,GRND1,0.0);COVAL(SMPLS,VSC2,GRND1,0.0) ENDIF + FIINIT(SC2)=FIINIT(SC1); RELAX(:CH1:,FALSDT,DTSC) + RELAX(SC1,FALSDT,DTSC); RELAX(SC2,FALSDT,DTSC) IF(:CH1:.EQ.TEM1) THEN PRNDTL(TEM1)=CONDFILE; STORE(PRPS);FIINIT(PRPS)=35 ** mat no. rho enul cp kond expan ** 1 air CSG10='q1' MATFLG=T;NMAT=1 35 1. 2.E-5 3.0 2.E-5 0 ENDIF ENDIF ** Expected values FLOW