TALK=T;RUN(1,1) PHOTON USE p up z;vec x 1 sh;pau;clear con p1 x 1 fi;.01;pau;clear con tem1 x 1 fi;.01;pau;cl ENDUSE DISPLAY The problem considered is laminar free convection of air between a pair of parallel, vertically-mounted flat plates of length H. These plates are maintained either at uniform heat fluxes (UHF) qw or uniform wall temperatures (UWT) tw. The solution domain has one plane of symmetry at the centre of the gap B between the two plates. The external pressure is the same at both the top and bottom of the plate, so the flow is driven entirely by buoyancy forces. The Boussinesq assumption is made in the simulations, and the flow is characterised by the Grashof number GrB and the gap-to-length ratio B/H. The solution domain comprises the gap between the two channel plates, as well as the free environment upstream and downstream of the channel. For economy, the solution domain may be restricted to the gap alone, although this approach is less accurate for developing flow because of the empirical representation of total pressure losses at the channel inlet and outlet. The practical application of free convection in vertical channels may be found in the electronics and telecommunications industry. The flow is fully developed if GrB*(B/H) < 1 for a UWT condition, and when GrB*(B/H) < 100 for a UHF condition (see Aung, Int.J. Heat Mass Transfer, Vol.15,p1577, 1972). Developing flow has been considered by Aung et al, Int.J.Heat Mass Transfer, Vol.15, p2293, 1972 & Morrone et al, Int.J.Heat Mass Transfer, Vol.40, No.5, p993, 1997). The dimensionless equations solved are: dW/dZ + dV/dY = 0 ; W*dZ/dZ + V*dV/dY = d/dY(dW/dY) + d/dZ(dW/dZ) - dP/DZ + GrB*T W*dT/dZ + V*dT/dY = (1./Pr)*d/dY(dT/dY) + (1./Pr)*d/dZ(dT/dZ) where Z = z/B ; Y = y/B ; W = w*B/enul ; V = v*B/enul P = (p-p,ref)*(B**2)/(rho*enul**2) T = k*(t-tref)/(qw*B) ; Pr = rho*enul*cp/k GrB = g*beta*qw*B**4/(k*enul**2) This Q1 may be used to run 6 cases which are documented in the literature. The results are summarised below in terms of the dimensionless volumetric flow rate PSI(=wbulk*B/enul): Developing Flow (UHF) --------------------- phoenics phoenics reduced domain full domain Morrone GrH=1.E5 B/H=0.5 19.0 27.0 30.0 GrH=1.E4 B/H=0.8 12.5 19.0 21.5 Fully-Developed Flow -------------------- phoenics Aung reduced & full domain GrB=1.E2 B/H=0.04 (UWT) 8.16 8.33 GrB=1.E2 B/H=0.04 (UHF) 14.80 17.13 where GrH=GrB*(H/B)**4a n The dimensionless volumetric flow rate produced by PHOENICS can be obtained from the RESULT file by taking TWICE the printed NETT source of R1 at INLET. ENDDIS ************************************************************ Group 1. Run Title and Number ************************************************************ ************************************************************ TEXT(Free Convection Between Vertical Plates ) ************************************************************ ************************************************************ IRUNN = 1 ;LIBREF = 254 ************************************************************ Group 2. Time dependence STEADY = T ************************************************************ Group 3. X-Direction Grid Spacing CARTES = T NX = 1 XULAST =1. XFRAC(1)=1. ************************************************************ Group 4. Y-Direction Grid Spacing NY = 55 YVLAST =1.5 YFRAC(1)=0.050764 ;YFRAC(2)=0.088385 YFRAC(3)=0.122251 ;YFRAC(4)=0.153888 YFRAC(5)=0.183964 ;YFRAC(6)=0.212852 YFRAC(7)=0.240788 ;YFRAC(8)=0.267935 YFRAC(9)=0.294409 ;YFRAC(10)=0.3203 YFRAC(11)=0.345677 ;YFRAC(12)=0.370597 YFRAC(13)=0.395104 ;YFRAC(14)=0.419237 YFRAC(15)=0.443027 ;YFRAC(16)=0.466501 YFRAC(17)=0.489684 ;YFRAC(18)=0.512595 YFRAC(19)=0.535254 ;YFRAC(20)=0.557674 YFRAC(21)=0.579872 ;YFRAC(22)=0.601859 YFRAC(23)=0.623647 ;YFRAC(24)=0.645247 YFRAC(25)=0.666667 ;YFRAC(26)=0.672294 YFRAC(27)=0.679596 ;YFRAC(28)=0.687699 YFRAC(29)=0.69637 ;YFRAC(30)=0.70549 YFRAC(31)=0.714985 ;YFRAC(32)=0.724803 YFRAC(33)=0.734907 ;YFRAC(34)=0.745267 YFRAC(35)=0.75586 ;YFRAC(36)=0.766668 YFRAC(37)=0.777674 ;YFRAC(38)=0.788865 YFRAC(39)=0.80023 ;YFRAC(40)=0.811758 YFRAC(41)=0.823442 ;YFRAC(42)=0.835272 YFRAC(43)=0.847243 ;YFRAC(44)=0.859347 YFRAC(45)=0.87158 ;YFRAC(46)=0.883935 YFRAC(47)=0.896409 ;YFRAC(48)=0.908996 YFRAC(49)=0.921694 ;YFRAC(50)=0.934498 YFRAC(51)=0.947405 ;YFRAC(52)=0.960411 YFRAC(53)=0.973514 ;YFRAC(54)=0.986712 YFRAC(55)=1. ************************************************************ Group 5. Z-Direction Grid Spacing PARAB = F NZ = 65 ZWLAST =3.75 ZFRAC(1)=0.030343 ;ZFRAC(3)=0.073072 ZFRAC(5)=0.109959 ;ZFRAC(7)=0.143924 ZFRAC(9)=0.175974 ;ZFRAC(11)=0.206618 ZFRAC(13)=0.236162 ;ZFRAC(15)=0.264806 ZFRAC(17)=0.292694 ;ZFRAC(19)=0.319932 ZFRAC(21)=0.339798 ;ZFRAC(23)=0.357493 ZFRAC(25)=0.37793 ;ZFRAC(27)=0.400115 ZFRAC(29)=0.423621 ;ZFRAC(31)=0.448204 ZFRAC(33)=0.473702 ;ZFRAC(35)=0.5 ZFRAC(37)=0.526298 ;ZFRAC(39)=0.551796 ZFRAC(41)=0.576379 ;ZFRAC(43)=0.599885 ZFRAC(45)=0.62207 ;ZFRAC(47)=0.642507 ZFRAC(49)=0.660202 ;ZFRAC(51)=0.669213 ZFRAC(53)=0.685063 ;ZFRAC(55)=0.712805 ZFRAC(57)=0.751212 ;ZFRAC(59)=0.799575 ZFRAC(61)=0.857398 ;ZFRAC(63)=0.924306 ZFRAC(65)=1. ************************************************************ Group 6. Body-Fitted Coordinates ************************************************************ Group 7. Variables: STOREd,SOLVEd,NAMEd ONEPHS = T NAME(1)=P1 ;NAME(5)=V1 NAME(7)=W1 ;NAME(148)=PRPS NAME(150)=TEM1 * Y in SOLUTN argument list denotes: * 1-stored 2-solved 3-whole-field * 4-point-by-point 5-explicit 6-harmonic averaging SOLUTN(P1,Y,Y,Y,N,N,Y) SOLUTN(V1,Y,Y,N,N,N,N) SOLUTN(W1,Y,Y,N,N,N,N) SOLUTN(PRPS,Y,N,N,N,N,Y) SOLUTN(TEM1,Y,Y,Y,N,N,N) PRPS = 148 ************************************************************ Group 8. Terms & Devices * Y in TERMS argument list denotes: * 1-built-in source 2-convection 3-diffusion 4-transient * 5-first phase variable 6-interphase transport TERMS(P1,Y,Y,Y,N,Y,Y) TERMS(V1,Y,Y,Y,Y,Y,Y) TERMS(W1,Y,Y,Y,Y,Y,Y) TERMS(TEM1,N,Y,Y,N,Y,N) DIFCUT =0. ;ZDIFAC =1. GALA = F ;ADDDIF = F ISOLX = -1 ;ISOLY = -1 ;ISOLZ = -1 ************************************************************ Group 9. Properties used if PRPS is not stored, and where PRPS = -1.0 if it is! RHO1 =1. ;TMP1 =0. ;EL1 =0. TSURR =0. ;TEMP0 =0. ;PRESS0 =0. DVO1DT =4096. ;DRH1DP =0. EMISS =0. ;SCATT =0. RADIA =0. ;RADIB =0. ENUL =1. ;ENUT =0. PRNDTL(V1)=1. ;PRNDTL(W1)=1. PRNDTL(TEM1)=-1.408451 PRT(V1)=1. ;PRT(W1)=1. PRT(TEM1)=1. CP1 =1. ;CP2 =1. ************************************************************ Group 10.Inter-Phase Transfer Processes ************************************************************ Group 11.Initial field variables (PHIs) FIINIT(P1)=1.0E-10 ;FIINIT(V1)=1.0E-10 FIINIT(W1)=0. ;FIINIT(PRPS)=-1. FIINIT(TEM1)=0. PATCH(PLATE ,INIVAL, 1, 1, 1, 25, 21, 50, 1, 1) INIT(PLATE ,PRPS,0. ,198. ) INIADD = F FSWEEP = 1 NAMFI =CHAM ************************************************************ Group 12. Patchwise adjustment of terms Patches for this group are printed with those for Group 13. Their names begin either with GP12 or & ************************************************************ Group 13. Boundary & Special Sources PATCH(HOCS ,CELL , 0, 0, 0, 0, 0, 0, 1, 1) COVAL(HOCS ,V1 , FIXFLU , GRND1 ) COVAL(HOCS ,W1 , FIXFLU , GRND1 ) PATCH(INLET ,LOW , 1, 1, 1, 55, 1, 1, 1, 1) COVAL(INLET ,P1 ,100. ,0. ) COVAL(INLET ,TEM1,0. ,0. ) PATCH(HEATFLUX,SWALL , 1, 1, 26, 26, 21, 50, 1, 1) COVAL(HEATFLUX,TEM1, FIXFLU ,1. ) PATCH(EXIT ,HIGH , 1, 1, 1, 55, 65, 65, 1, 1) COVAL(EXIT ,P1 ,100. ,0. ) COVAL(EXIT ,TEM1,0. ,0. ) PATCH(FREEBH ,SOUTH , 1, 1, 1, 1, 51, 65, 1, 1) COVAL(FREEBH ,P1 ,100. ,0. ) COVAL(FREEBH ,TEM1,0. ,0. ) PATCH(BUOY ,PHASEM, 1, 1, 1, 55, 1, 65, 1, 1) COVAL(BUOY ,W1 , FIXFLU , GRND3 ) XCYCLE = F EGWF = T WALLCO = GRND2 BUOYA =0. ; BUOYB =0. ; BUOYC =-1. ************************************************************ Group 14. Downstream Pressure For PARAB ************************************************************ Group 15. Terminate Sweeps LSWEEP = 800 ;ISWC1 = 1 LITHYD = 1 ;LITFLX = 1 ;LITC = 1 ;ITHC1 = 1 SELREF = T RESFAC =1.0E-05 ************************************************************ Group 16. Terminate Iterations LITER(P1)=50 ;LITER(V1)=10 LITER(W1)=10 ;LITER(TEM1)=50 ENDIT(P1)=GRND1 ;ENDIT(V1)=1.0E-03 ENDIT(W1)=1.0E-03 ;ENDIT(TEM1)=1.0E-03 ************************************************************ Group 17. Relaxation RELAX(P1,LINRLX,1.) RELAX(V1,FALSDT,3.493856) RELAX(W1,FALSDT,3.493856) RELAX(PRPS,LINRLX,1.) RELAX(TEM1,FALSDT,1.0E+09) OVRRLX =0. EXPERT = F ;NNORSL = F ************************************************************ Group 18. Limits VARMAX(P1)=1.0E+10 ;VARMIN(P1)=-1.0E+10 VARMAX(V1)=1.0E+06 ;VARMIN(V1)=-1.0E+06 VARMAX(W1)=1.0E+06 ;VARMIN(W1)=-1.0E+06 VARMAX(PRPS)=1.0E+10 ;VARMIN(PRPS)=-1.0E+10 VARMAX(TEM1)=1.0E+10 ;VARMIN(TEM1)=-1.0E+10 ************************************************************ Group 19. Data transmitted to GROUND PARSOL = F ISG62 = 1 SPEDAT(SET,SCHEME,INLCS005,I,1) SPEDAT(SET,SCHEME,INLCS007,I,1) SPEDAT(SET,GXMONI,PLOTALL,L,T) SPEDAT(SET,MATERIAL,198,L,T) ************************************************************ Group 20. Preliminary Printout DISTIL = T ;NULLPR = F NDST = 0 DSTTOL =1.0E-02 EX(P1)=125.400002 ;EX(V1)=1.595 EX(W1)=9.028 ;EX(PRPS)=0.7902 EX(TEM1)=0.04486 ************************************************************ Group 21. Print-out of Variables INIFLD = F ;SUBWGR = F * Y in OUTPUT argument list denotes: * 1-field 2-correction-eq. monitor 3-selective dumping * 4-whole-field residual 5-spot-value table 6-residual table OUTPUT(P1,Y,N,Y,Y,Y,Y) OUTPUT(V1,Y,N,Y,Y,Y,Y) OUTPUT(W1,Y,N,Y,Y,Y,Y) OUTPUT(PRPS,Y,N,Y,N,N,N) OUTPUT(TEM1,Y,N,Y,Y,Y,Y) ************************************************************ Group 22. Monitor Print-Out IXMON = 1 ;IYMON = 54 ;IZMON = 64 NPRMON = 100000 ;NPRMNT = 1 ;TSTSWP = -1 UWATCH = T ;USTEER = T HIGHLO = F ************************************************************ Group 23.Field Print-Out & Plot Control NPRINT = 100000 ;NUMCLS = 5 NYPRIN = -1 ;IYPRF = 1 ;IYPRL = 10000 NZPRIN = 2 ;IZPRF = 1 ;IZPRL = 10000 XZPR = F ;YZPR = F IPLTF = 1 ;IPLTL = -1 ;NPLT = 10 ISWPRF = 1 ;ISWPRL = 100000 ITABL = 3 ;IPROF = 1 ABSIZ =0.5 ;ORSIZ =0.4 NTZPRF = 1 ;NCOLPF = 50 ICHR = 2 ;NCOLCO = 45 ;NROWCO = 20 No PATCHes yet used for this Group ************************************************************ Group 24. Dumps For Restarts SAVE = T ;NOWIPE = F NSAVE =CHAM STOP