AUTOPLOT USE file phi 5 da 1 u2;screen;msg 2nd-phase velocity;pl 1 msg pressto continue pause cl;screen;msg 2nd-phase volume fraction;da 1 r2;pl 1 msg press to continue pause cl msg press e to END enduse TEXT(1D PARTICLE FLOW IN UNIFORM GAS STREAM TITLE DISPLAY The case considered is the acceleration of particles by a uniform flowing gas stream. The flow is steady, one dimensional and it is assumed that there is no particle interaction. The analytical solution for this case has been given by Morsi and Alexander (JFM, Vol.55, p193, 1972). The free-stream velocity is not affected by the particles owing to their very low concentration. The density ratio is taken as 2000, the particle diameter as 500 microns, and the particle Reynolds number as 3,000. The calculation may be performed in the x-, y- or z-direction with phase 1 as carrier (gas) and phase 2 as dispersed (solid) or vice versa (CONPHS=2). ENDDIS The analytical solution does not provide an explicit expression for the particle velocity field as a function of distance, even when it is simplified, as in the present case, by presuming that the interphase drag coefficient is constant. Therefore, PHOENICS is validated by performing the calculation over a domain length computed analytically (2m) for a given value of the outlet particle velocity. The predicted particle outlet velocity compares very well with the value (3m/s) selected for the analytical calculation of the domain length. * CONPHS=1 selects 1st phase as the continuous ( gas ) phase and thus CFIPS=GRND7 * =2 selects 2nd phase as the continuous ( gas ) phase and thus CFIPS=GRND8 * VARLAM=T tests coding in GXCFIP when ENUL is variable * VARDEN=T tests coding in GXCFIP when carrier RHO is variable BOOLEAN(VARLAM,VARDEN);INTEGER(CONPHS);VARLAM=T;CONPHS=1;VARDEN=T * for 1dx calculation set: CH1=X;CH2=U1;CH3=U2 * for 1dy calculation set: CH1=Y;CH2=V1;CH3=V2 * for 1dz calculation set: CH1=Z;CH2=W1;CH3=W2 CHAR(CH1,CH2,CH3);CH1=X;CH2=U1;CH3=U2 CH1=Y;CH2=V1;CH3=V2 CH1=Z;CH2=W1;CH3=W2 REAL(XLEN,UGAS,UINP,UIN1,UIN2,R1IN,R2IN,REYP,DIAMP,DENRAT) DIAMP=5.E-4;REYP=3000;XLEN=2.0;UGAS=5.0;UINP=1.0;DENRAT=2000. ** select uoutp and compute xlen REAL(UOUTP,CD,VREL,ETA,AONE,TERM1,TERM2,FLOW1,FLOW2) UOUTP=3.0;VREL=UGAS-UINP CD=24.*(1.+.15*REYP**.687)/REYP+.42/(1.+4.25E4/(REYP**1.16)) AONE=3.*CD/(4.*DIAMP*DENRAT);TERM1=(UOUTP-UGAS)/(UINP-UGAS) TERM1=(UOUTP-UGAS)/(UINP-UGAS) TERM2=UGAS*(UINP-UOUTP)/((UOUTP-UGAS)*(UINP-UGAS)) XLEN=(LOG(TERM1)-TERM2)/AONE reyp cd xlen IF(CONPHS.EQ.1) THEN + UIN1=UGAS;UIN2=UINP;R2IN=1.E-5;R1IN=1-R2IN ELSE + UIN1=UINP;UIN2=UGAS;R1IN=1.E-5;R2IN=1-R1IN ENDIF GROUP 1. Run title and other preliminaries GROUP 2. Transience; time-step specification GROUP 3. X-direction grid specification GRDPWR(:CH1:,-20,XLEN,1.4) GROUP 4. Y-direction grid specification GROUP 5. Z-direction grid specification GROUP 6. Body-fitted coordinates or grid distortion GROUP 7. Variables stored, solved & named ONEPHS=F;SOLVE(P1,:CH2:,:CH3:,R1,R2) Activate storage for printout of interphase drag properties STORE(REYN,VREL,CD,APRJ,CFIP,SIZE) GROUP 8. Terms (in differential equations) & devices GROUP 9. Properties of the medium (or media) IF(CONPHS.EQ.1) THEN + RHO1=1.0;RHO2=DENRAT*RHO1 ELSE + RHO2=1.0;RHO1=DENRAT*RHO2 ENDIF ENULA=VREL*DIAMP/REYP IF(VARLAM) THEN Use ENUL=ENULA+ENULB*TMP1 + STORE(TMP1);ENUL=LINTEM;ENULB=0.0;TMP1=CONST;TEMP0=273 ELSE + ENUL=ENULA ENDIF GROUP 10. Inter-phase-transfer processes and properties IF(CONPHS.EQ.1) THEN + CFIPS=GRND7 ELSE + CFIPS=GRND8 ENDIF ** CFIPA = minimum slip velocity CFIPB = particle size CFIPA=0.01;CFIPB=DIAMP GROUP 11. Initialization of variable or porosity fields FIINIT(:CH2:)=UIN1;FIINIT(:CH3:)=UIN2 FIINIT(R1)=R1IN;FIINIT(R2)=R2IN GROUP 12. Unused GROUP 13. Boundary conditions and special sources FLOW1=RHO1*UIN1*R1IN;FLOW2=RHO2*UIN2*R2IN INLET(IN,CELL,$1,$1,$1,$1,$1,$1,1,1) VALUE(IN,P1,FLOW1);VALUE(IN,:CH2:,UIN1) VALUE(IN,P2,FLOW2);VALUE(IN,:CH3:,UIN2) OUTLET(OUT,CELL,%1,%1,%1,%1,%1,%1,1,1) ** estimate particle outflow velocity, and then use value so as to allow for slip in exit cell outflow UOUTP=3.0 IF(CONPHS.EQ.1) THEN + COVAL(OUT,P1,RHO1*1.E2,0);COVAL(OUT,P2,RHO2*1.E2*UOUTP/UIN1,0) ELSE + COVAL(OUT,P1,RHO1*1.E2*UOUTP/UIN2,0);COVAL(OUT,P2,RHO2*1.E2,0) ENDIF GROUP 15. Termination of sweeps LSWEEP=60 RESREF(P1)=1.E-12*(FLOW1+FLOW2) RESREF(R1)=1.E-12*FLOW1;RESREF(R2)=1.E-12*FLOW2 RESREF(:CH2:)=RESREF(R1)*UIN1;RESREF(:CH3:)=RESREF(R2)*UIN2 GROUP 16. Termination of iterations GROUP 17. Under-relaxation devices RELAX(R1,LINRLX,1.0);RELAX(R2,LINRLX,1.0) GROUP 18. Limits on variables or increments to them GROUP 19. Data communicated by satellite to GROUND GROUP 20. Preliminary print-out GROUP 21. Print-out of variables NXPRIN=1;NYPRIN=1;NZPRIN=1 GROUP 22. Spot-value print-out IF(:CH1:.EQ.X) THEN + IXMON=NX/2;IZMON=1;IYMON=1 ELSE + IZMON=NZ/2;IXMON=1;IYMON=1 ENDIF IF(:CH1:.EQ.Y) THEN + IYMON=NY/2;IXMON=1;IZMON=1 ENDIF TSTSWP=-1 GROUP 23. Field print-out and plot control GROUP 24. Dumps for restarts IF(VARDEN) THEN IF(CONPHS.EQ.1) THEN + RHO1A=RHO1;RHO1B=0.0;RHO1=LINTEMP ELSE + STORE(TMP2);TMP2=CONST;RHO2A=RHO2;RHO2B=0.0;RHO2=LINTEMP ENDIF ENDIF