AUTOPLOT USE file p3 5 p6 p9 p12 da 1 pt1 da 2 pt1 da 3 pt1 da 4 pt1 screen msg volume fraction of gas along length of duct at t=45s blb1 1 pl 1 msg pressto continue pause screen msg volume fraction of gas along length of duct at t=90s blb1 2 pl 2 msg press to continue pause screen msg volume fraction of gas along length of duct at t=135s blb1 3 pl 3 msg press to continue pause screen msg volume fraction of gas along length of duct at t=180s blb1 4 pl 4 msg press e to END enduse GROUP 1. Run title and other preliminaries TEXT(Trans. phase separation of gas/liq:P112 TITLE DISPLAY 1D TRANSIENT PHASE SEPARATION OF GAS & LIQUID 1-dimensional (x), transient, elliptic simulation This case calculates the separation of gas and liquid which at the start of the calculation are uniformly mixed in a closed duct. Under the influence of gravity, the lighter phase (gas) starts to rise at a constant slip velocity which is assumed to be the terminal velocity. The liquid is consequently displaced downwards. +------------+ ^ | gas | | | + | |x | liquid | +------------+ enddis GROUP 2. Transience; time-step specification STEADY=F lstep=40; tlast=600.0 nx=20; xulast=1.0; ny=1; yvlast=1.0; nz=1; zwlast=1.0 #unigrid char(setaslp); setaslp=$P001 #setaslp GROUP 9. Properties of the medium (or media) STORE(DEN1,VISL) * The mixture density is calculated in GROUND. RHO2=1000.0 * The fluid viscosity is calculated in GROUND enula=1.e-6;enul=ENULA;PRNDTL(PT0)=ENULA GROUP 11. Initialization of variable or porosity fields FIINIT(PT0)=0.5;FIINIT(PT1)=0.5;FIINIT(P1)=0.0 GROUP 13. Boundary conditions and special sources PHINT(PT1)=1.0; CINT(PT1)=1.e-4 PATCH(REFP1,CELL,NX,NX,1,1,1,1,1,LSTEP) COVAL(REFP1,P1,FIXP,0.0) buoya=-9.81 patch(buoy,phasem,1,nx,1,ny,1,nz,1,lstep) coval(buoy,u1,fixflu,DENSITY) GROUP 15. Termination of sweeps LSWEEP=25;RESREF(P1)=1.E-20;RESREF(PT1)=1.E-20 GROUP 16. Termination of iterations LITER(PT0)=5; LITER(PT1)=10 ENDIT(PT0)=1.E-6; ENDIT(PT1)=1.E-8 RELAX(PT0,LINRLX,0.5); RELAX(PT1,LINRLX,0.3) GROUP 17. Under-relaxation devices relax( u1,falsdt,1.e1) GROUP 21. Print-out of variables OUTPUT(P1,Y,Y,Y,Y,Y,Y);OUTPUT(PT1,Y,Y,Y,Y,Y,Y) OUTPUT(W1,Y,Y,Y,Y,Y,Y) SPEDAT(SET,GXMONI,TRANSIENT,L,F) GROUP 22. Spot-value print-out TSTSWP=-1;IXMON=NX GROUP 23. Field print-out and plot control IPLTF=2;IPLTL=LSWEEP;XZPR=T;IPROF=1 GROUP 24. Dumps for restarts ixprf=1;ixmon=1;NXPRIN=1;NZPRIN=1 idispa=3;csg1=p;ASLP=T;lstep=12