GROUP 1. Run title and other preliminaries TEXT(VAN DRIEST_2D PARAB BOUNDARY LAYER :T202 TITLE DISPLAY The problem considered is steady, incompressible, turbulent plane flow along a smooth flat plate with zero pressure gradient. The plate is maintained at a constant temperature above that of the free stream. The calculations are started 0.487 metres downstream of the leading edge, corresponding to a length Reynolds number REx of 1.E6. The initial mean- velocity profile is taken from published experimental data, and the initial turbulence-energy profile is estimated from the local friction velocity by assuming a distribution compatible with that measured in the fully- developed boundary layer. ENDDIS In case 190, the Prandtl mixing-length turbulence model is used and the mixing-length distribution is prescribed according to the Escudier formulae, ie Lm=k*y for y/d<<0.09/k, and Lm= 0.09*d for y/d>0.09. Here k is the von Karman's constant and y is the normal distance from the wall. The turbulent Prandtl number is set equal to 0.86 and the molecular Prandtl number to 0.71. The user may set REYLOW=T to activate van Driest's extension to the mixing-length model so as to integrate right down to the wall and perform a low-Reynolds-number-model calculation of the turbulent boundary. For this purpose 100 cells have been located across the boundary layer, rather than with the 20 cells used for the standard mixing-length model. A forward step size of 30% of the local width of the boundary layer is used together with 100 forward steps. Consequently, the marching integration is terminated at a length Reynolds number of about 2.1E6. Experimental data indicates that the local skin friction coefficient Cf is fairly well described by the Schultz-Grunow correlation, i.e. Cf = 0.37*(LOG10(REx))**-2.58 where Cf = 2.*TAUW/(RHOFRE*WFREE**2). For REx=2.1E6 this correlation yields Cf=3.17E-3, while the present PHOENICS van-Driest predictions yield Cf=3.23E-3. AUTOPLOT USE file phi 5 clear da 1 w1;col3;plot 1 @ 0.10254E+03 0.26250E+04 CR W1(m/s)@ @ 0.18969E+04 0.16284E+03 CR Distance across the Boundary Layer(m)@ msg Press e to END ENDUSE REAL(YINLET,WFREE,DELTIN,ZO,AK,CFEXPT,GPOWER,TFREE,TWALL,POW) YINLET=0.0115;WFREE=33.0;DELTIN=0.009923;ZO=0.487;AK=0.41 CFEXPT=3.381E-3;GPOWER=0.85;TFREE=5.;TWALL=10.;POW=0.2345 GROUP 4. Y-direction grid specification BOOLEAN(REYLOW,VARLAM); REYLOW=T;VARLAM=F IF(REYLOW) THEN + NY=100;GRDPWR(Y,NY,YINLET,1.5) ** activate van Driest extension to the mixing length + IENUTA=5 ELSE + NY=22;YVLAST=YINLET + YFRAC(1)=5.000E-02;YFRAC(2)=6.200E-02 + YFRAC(3)=7.400E-02;YFRAC(4)=1.070E-01 + YFRAC(5)=1.450E-01;YFRAC(6)=1.860E-01 + YFRAC(7)=2.290E-01;YFRAC(8)=2.750E-01 + YFRAC(9)=3.220E-01;YFRAC(10)=3.720E-01 + YFRAC(11)=4.230E-01;YFRAC(12)=4.760E-01 + YFRAC(13)=5.300E-01;YFRAC(14)=5.850E-01 + YFRAC(15)=6.410E-01;YFRAC(16)=6.990E-01 + YFRAC(17)=7.570E-01;YFRAC(18)=8.160E-01 + YFRAC(19)=8.770E-01;YFRAC(20)=9.380E-01 + YFRAC(21)=9.690E-01;YFRAC(22)=1.000E+00 ENDIF AZYV=GPOWER;ZWADD=ZO GROUP 5. Z-direction grid specification PARAB=T;NZ=100;AZDZ=PROPY GROUP 7. Variables stored, solved & named NAME(H1)=TEMP;SOLVE(P1,V1,W1,TEMP);STORE(ENUT,LEN1) GROUP 8. Terms (in differential equations) & devices DIFCUT=0.0;TERMS(TEMP,N,Y,Y,Y,Y,Y) GROUP 9. Properties of the medium (or media) RHO1=1.0;ENUL=1.5E-5 ** Select Mixing-Length Formula : Group 9/Sect. 5 of GREX3 EL1=MIXLENBL;ENUT=MIXLEN;EL1A=0.0;EL1B=AK PRT(TEMP)=0.86;PRNDTL(TEMP)=0.7 ** test for ground-set enul ENULA=ENUL IF(VARLAM) THEN + TMP1=CONST;TMP1A=0.0;ENUL=LINTEM ENDIF GROUP 11. Initialization of variable or porosity fields FIINIT(W1)=WFREE;FIINIT(TEMP)=TFREE GROUP 13. Boundary conditions and special sources ** South Wall Boundary WALL(WFUN,SOUTH,1,1,1,1,1,NZ,1,1);COVAL(WFUN,TEMP,LOGLAW,TWALL) **North Free Boundary PATCH(FREE,NORTH,1,1,NY,NY,1,NZ,1,1) COVAL(FREE,P1,1.E5,0.0);COVAL(FREE,TEMP,ONLYMS,TFREE) COVAL(FREE,W1,ONLYMS,WFREE);COVAL(FREE,V1,ONLYMS,0.0) ** Inlet Boundary PATCH(PROF,LOW,1,1,1,NY,1,1,1,1) COVAL(PROF,P1,FIXFLU,GRND3);COVAL(PROF,W1,ONLYMS,GRND3) COVAL(PROF,TEMP,ONLYMS,GRND3);COVAL(PROF,V1,ONLYMS,0.0) GROUP 14. Downstream pressure for PARAB=T IPARAB=1 GROUP 16. Termination of iterations LITHYD=8 GROUP 19. Data communicated by SATELLITE to GROUND TEMP0=TWALL;PROFA=CFEXPT;PROFB=DELTIN;PROFC=POW;PROFD=WFREE DWDY=T;DZW1=0.3 EL1C = velocity fraction for layer-width calculation EL1D = free stream velocity for layer-width calculation EL1E = 0.0 for layer-width calculation EL1C=0.005;EL1D=WFREE;EL1E=0.0 GROUP 22. Monitor print-out NPRMON=4;IYMON=3;NPLT=1;IPLTL=LITHYD;TSTSWP=-1 GROUP 23. Field print-out and plot control PATCH(IZEQNZ,PROFIL,1,1,1,NY,NZ,NZ,1,1);PLOT(IZEQNZ,W1,0.0,0.0) PLOT(IZEQNZ,TEMP,0.0,0.0);PLOT(IZEQNZ,LEN1,0.0,0.0) NYPRIN=2;NZPRIN=NZ;ORSIZ=0.4 GROUP 24. Dumps for restarts NYPRIN=1