TEXT(CHEMKIN-1DY Plug Flow H2-O2 Reactor 201 DISPLAY The example considered is the steady combustion of an H2-O2-N2 mixture in a 1d plug-flow reactor (PSR) at atmospheric pressure. The case is a steady-state emulation of the transient zero-d PSR test case described in the CHEMKIN SANDIA Report 'PSR: A Fortran program for modelling well-stirred reactors', P.Glarborg et al, SAND86-8209, (1992). Species diffusion and heat conduction are absent. As with all CHEMKIN calculations, cgs units are used. The first cell is intended to represent the reactor volume of 67.4cm^3, and the nominal residence time is 0.03msec. The inlet mass flow rate is 364g/s and the inlet mole fractions are: H2=0.275; O2=0.1375; and N2=0.5875. The inlet temperature is 298K and there is no heat loss from the reactor. The H2-O2 reaction mechanism, which is defined in the file HO11.CKM, is simpler than that used in the SANDIA report. The reaction scheme used is taken from; "Numerical Methods in Laminar Flame Propagation", Vol. 6, Notes on Numerical Fluid Mechanics, Ed. Peters, N. & Warnatz, J. (1992). ENDDIS The results obtained in the 1st cell agree adequately the following values taken from the SANDIA PSR report: exit mol fractions O = 1.54E-2 O2 = 3.48E-2 H = 6.75E-2 H2 = 5.80E-2 OH = 1.34E-2 HO2 = 9.27E-6 H2O = 0.192 H2O2 = 2.23E-5 N2 = 0.619 temperature = 1700 K (fixed) The run is set up so that the calculation may be performed either with the CHEMKIN PBP TWOPNT solver (the default), or alternatively with the PHOENICS solver. GROUP 1. Run title and other preliminaries MESG( TEXT(CHEMKIN-1DY Plug Flow H2-O2 Reactor 201 REAL(DTF,DTC,FLORAT,REAVOL,YH2IN,YO2IN,YLEN) BOOLEAN(TWOPNT) MESG( Do you want to use CHEMKIN TWOPNT solver? (y/n) READVDU(ANS,CHAR,Y) IF(:ANS:.EQ.Y) THEN + TWOPNT=T + MESG(CHEMKIN PBP SOLVER activated ELSE + TWOPNT=F + MESG(PHOENICS SOLVER activated ENDIF GROUP 2. Transience; time-step specification STEADY=T GROUP 3. X-direction grid specification REAVOL=67.4;GRDPWR(X,1,REAVOL,1.0) GROUP 4. Y-direction grid specification NY=2;YLEN=2.0;GRDPWR(Y,NY,YLEN,1.0) GROUP 7. Variables stored, solved & named ** conduction terms removed from energy equation SOLVE(P1,V1);STORE(DEN1);SOLVE(TEM1);TERMS(TEM1,N,P,N,P,Y,N) ** store: elemental mass fractions of H, N & O; the heat release rate per unit volume; and the mean effective specific heat of the mixture STORE(ELH,ELN,ELO,QDOT,SPH1) INTEGER(KK,JJ);KK=8;ARRAY(CIN,REAL,KK) CHEMKIN(SPECIES,H2,H,O2,O,OH,HO2,H2O,N2) ** CHEMKIN(SPECIES,... sets CHSOB=16 (=C1) & LSG61=T CHSOB = PHOENICS Variable No of 1st CHEMKIN species LSG61 = T activates calls to GXCHKI from GREX3 ** Diffusion terms removed from mass-fraction equations DO II=1,KK-1 + JJ=II+CHSOB-1 + TERMS(C:JJ:,N,P,N,P,Y,N) ENDDO GROUP 9. Properties of the medium (or media) CP1=GRND9; RHO1=CHEMIST ** Sets the reference pressure CHSOC (in Atmospheres) and CSG4='ho11' which identifies the CHEMKIN link file: ho11ckln; and the transport-properties link file: ho11mcln. CHEMKIN(PROP,ho11,1.0) GROUP 11. Initialization of variable or porosity fields DO II=1,KK + JJ=II+CHSOB-1 + FIINIT(:JJ:)=0.0 ENDDO YH2IN=0.025701;YO2IN=0.205607; FIINIT(H2)=YH2IN; FIINIT(O2)=YO2IN REAL(SUMY,MDOT);SUMY=0.0 DO II=1,KK-1 + JJ=II+CHSOB-1 + SUMY=SUMY+FIINIT(:JJ:) ENDDO FIINIT(N2)=1.-SUMY; FIINIT(TEM1)=1700. DO II=1,KK + JJ=II+CHSOB-1 + CIN(:II:)=FIINIT(:JJ:) ENDDO ** initialise the density field PATCH(ICHEMK1,INIVAL,1,NX,1,NY,1,NZ,1,1) INIT(ICHEMK1,DEN1,0.0,GRND1) GROUP 13. Boundary conditions and special sources ** FLORAT=364.0;MDOT=FLORAT/REAVOL INLET(NOCPCK1,SOUTH,1,NX,1,1,1,NZ,1,LSTEP) VALUE(NOCPCK1,P1,MDOT); VALUE(NOCPCK1,V1,GRND9) VALUE(NOCPCK1,TEM1,GRND9);TMP1A=298. DO II=1,KK + JJ=II+CHSOB-1 + VALUE(NOCPCK1,:JJ:,CIN(:II:)) ENDDO OUTLET(OUT1,NORTH,1,NX,NY,NY,NZ,NZ,1,LSTEP); VALUE(OUT1,P1,0.0) IF(TWOPNT) THEN ** Activate the implicit TWOPNT PBP algorithm for the energy and species equations, i.e. CHSOA=GRND9 + CHEMKIN(REACT,TWOPNT,TEM1) ELSE + CHEMKIN(REACT,PHOENICS,TEM1) ENDIF GROUP 15. Termination of sweeps IF(TWOPNT) THEN + LSWEEP=40;NPLT=5;TSTSWP=-1 ELSE + LSWEEP=1000;NPLT=50;TSTSWP=-50 ENDIF GROUP 16. Termination of iterations DO II=1,KK + JJ=II+CHSOB-1 + ENDIT(:JJ:)=1.E-6 ENDDO ENDIT(TEM1)=1.E-10 GROUP 17. Under-relaxation devices DTF=3.E-5; RELAX(V1,FALSDT,DTF); VARMIN(TEM1)=200.;DENPCO=T NB: SELREF=F in CHEMKIN interface if TWOPNT solver activated. IF(TWOPNT) THEN + DTC=10.*DTF + RESREF(TEM1)=-1.E-3; RELAX(TEM1,FALSDT,DTF) ELSE ** set FIXVAL=1.E15 to prevent solution cut-out of TEM1 + FIXVAL=1.E15;DTC=2.*DTF + RELAX(TEM1,FALSDT,0.007*DTF) ENDIF DO II=1,KK + JJ=II+CHSOB-1 + RELAX(:JJ:,FALSDT,DTC) ENDDO GROUP 19. Data communicated by satellite to GROUND ** The link files ho11ckln & ho11mcln were created from the mechanism link file HO11.CKM, which has the form: ELEMENTS O H N END SPECIES H2 H O2 O OH HO2 H2O N2 END REACTIONS JOULES/MOLE H2 + OH = H2O + H 2.2E13 0.0 21.5E3 O2 + H = O + OH 2.2E14 0.0 70.3E3 H2 + O = H + OH 1.8E10 1.0 37.2E3 OH + OH = H2O + O 6.3E12 0.0 4.6E3 H + H + M = H2 + M 6.4E17 -1.0 0.0 OH + H + M = H2O + M 5.0E16 0.0 0.0 O2 + H + M = HO2 + M 1.4E15 0.0 7.9E3 HO2 + H = OH + OH 2.5E14 0.0 7.9E3 HO2 + H = H2 + O2 2.5E13 0.0 2.9E3 OH + HO2 = H2O + O2 1.5E13 0.0 0.0 HO2 + O = O2 + OH 6.3E13 0.0 2.9E3 END ** ** The link files ho11ckln, ho11mcln & ho11.ckm reside in the directory: d_earth\d_opt\d_chem. GROUP 20. Preliminary print-out ECHO=T GROUP 22. Spot-value print-out ITABL=3; OUTPUT(DEN1,Y,Y,Y,Y,Y,Y) GROUP 24. Dumps for restarts INIFLD=T;IYMON=1;NYPRIN=1