DISPLAY
A hydrocarbon fuel enters steadily a duct of uniform cross-
section steadily, through the porous wall of which is supplied a
steady stream of air, at a low rate for the first 3/4 of the
length, and at an increased rate over the last 1/4 .
The air and fuel are supposed to react in a mixed-is-burned
manner; but smoke is presumed to be generated at a rate which is
proportional to the concentration of unburned fuel times the
absolute temperature raised to the power SMOEXP.
The multi-fuel model of turbulence is used, but with
arbitrarily chosen values of the micro-mixing rate, CONMIX * RATE.
The situation is discussed in the
report by DB Spalding, dated 1998
ENDDIS
************************************************************
PHOTON USE
AUTOPLOT
file; phi 5
cl; da 1; prod; da 1; oxid; da 1; fuel; scale; cola 1; col3 2
colf 3
msg mass fractions of prod - yellow, oxid - blue, free fuel -red
msg
msg flow is from left to right
pause
cl; da 1; smos; da 1; smom; f11; scale; cola 1; col3 2;
msg mass fractions of smoke according to:
msg
msg single-fluid - yellow; multi-fluid - blue
pause
cl; da 1; f1; da 1; f10; da 1; f20; scale; cola 1; col3 2; colf 3
msg mass fractions of f1 - yellow, f10 - blue, f20 - red
pause
cl; da 1; f1; da 1; f3; da 1; f5; da 1; f7; da 1; f9; da 1; f11;
da 1; f13; da 1; f15; da 1; f17; da 1; f19; da 1; f20; scale;
cola 1; col1 2; col1 3; col1 4; col1 5; col3 6; col1 7;
col1 8; col1 9; col1 10; colf 11
msg mass fractions of some intermediate fluids also
pause
cl; da 1; mnsq; cola 1
msg root-mean-square fluctuations
pause
cl; da 1; tmp1; cola 1 ; da 1; tmpm; col3 2
msg temperatures: single fluid - yellow; multi-fluid - blue
pause
cl; da 1; fuel; cola 1; da 1; frfm; col3 2;
msg free fuel from single- (yellow) and multi-fluid models (blue)
pause
enduse
TEXT(1D Smoke-Generation with MFM
TITLE
NX=50; XULAST=1; YVLAST=0.1
nx=4
#unigrid
Declarations of non-standard variables
REAL(WAIR,WFU,WPR,STOIC,FSTOI,CPAIR,CPPR,CPFU,HFU,TOXID,TFUEL)
REAL(HFUIN,UINF,RHAIN,RHFIN,FINF,HAIRIN,TSTOIC)
Settings of these and other variables
WAIR=29.0; WFU=16.0; WPR=28.0 ! molecular weights
STOIC=17.24 ! stoichiometric air/fuel ratio
FSTOI=1./(1.+ STOIC) ! stoichiometric mixture fract.
CPAIR=1.5E3; CPPR=1.5E3; CPFU=1.5E3 ! specific heats
HFU=4.9E7 ! heat of reaction
TOXID=773.0; TFUEL=773.0 ! inflow-stream temperatures
HAIRIN=CPAIR*TOXID ! & resulting enthalpy
UINF=2.0 ! fuel-inflow velocity m/s
FINF=1.0 ! and fuel mass fraction
! in fuel-bearing stream
RHAIN=1.0 * 273.0 / TOXID ! densities of inflow
RHFIN = RHAIN * WFU / WAIR ! streams
PRESS0=1.0E5 ! pressure is 1 atmosphere
Group 7: variables to be solved and stored
SOLVE(P1,U1,H1,MIXF) ! FUEL need not be solved, because deduced
STORE(RATE,FUEL,OXID,PROD,TMP1,RHO1,SPH1) ! from MIXF .. see SCRSEQ
GROUP 8. Terms (in differential equations) & devices
TERMS(H1,N,Y,Y,N,Y,N) ! switch off kinetic heat source
DENPCO=T
Group 9: other property settings
data settings relating to density, temperature & specific heat
RHO1=3GASES ! select density to be computed in gxdens; igrnd=6
RHO1A=WFU; RHO1B=WAIR; RHO1C=WPR ! transmit necessary constants
TMP1=SCRSEQ ! select density to be computed in gxtempr; igrnd=7
! fixes concentrations to fit thermodynamic equilib.
TMP1A=CPFU; TMP1B=CPPR; TMP1C=CPAIR ! transmit necessary constants
CP1=GRND10 ! select sp. heat to be computed in gxspehe; igrnd=10
CP1A=CPFU; CP1B=CPAIR; CP1C=CPPR ! transmit necessary constants
HFUIN=CPFU*TFUEL + HFU * (FINF-FSTOI) /(1.0 - FSTOI) ! & resulting
TSTOIC = TOXID + (FSTOI/FINF) * HFUIN / CPAIR ! values
TMP2A=FSTOI; TMP2B=HFU ; TMP2C=FINF ! transmit necessary constants
GROUP 11: Initial values
FIINIT(RHO1)=RHAIN; FIINIT(H1)=HAIRIN; FIINIT(MIXF)=FINF
FIINIT(FUEL)=FINF; FIINIT(U1)=UINF
GROUP 13. Boundary conditions and special sources
** Fuel inlet
PATCH(FUIN,WEST,1,1,1,1,1,1,1,1)
COVAL(FUIN,P1,FIXFLU,RHFIN*UINF)
COVAL(FUIN,U1,ONLYMS,UINF)
COVAL(FUIN,MIXF,ONLYMS,1.0) ! stream is pure fuel, hence the 1.0
COVAL(FUIN,H1,ONLYMS,HFUIN)
** Outlet Boundary
PATCH(OUTLET,EAST,NX,NX,1,1,1,1,1,1)
COVAL(OUTLET,P1, 1.0, 0.0)
** Air inlet
PATCH(AIRIN,NORTH,1,NX,1,1,1,1,1,1)
COVAL(AIRIN,P1,FIXFLU,1.4*RHAIN*UINF)
COVAL(AIRIN,H1,ONLYMS,HAIRIN)
** second air inlet
PATCH(AIRIN2,NORTH,3*NX/4,NX,1,1,1,1,1,1)
COVAL(AIRIN2,P1,FIXFLU,40*RHAIN*UINF)
COVAL(AIRIN2,H1,ONLYMS,HAIRIN)
GROUP 15. Termination of sweeps
LSWEEP=1000
GROUP 16. Termination of iterations
LITER(P1)=20; LITER(U1)=20; LITER(V1)=20; LITER(W1)=20
GROUP 17. Under-relaxation devices
RELAX(RHO1,LINRLX,0.1); RELAX(P1,LINRLX,0.5)
GROUP 18. Limits on variables or increments to them
VARMIN(TMP1)=TOXID
VARMIN(RHO1)=0.1*RHAIN
VARMAX(RHO1)=2.0*RHAIN
GROUP 19. Data communicated by satellite to GROUND
TMP2A=FSTOI; TMP2B=HFU
GROUP 21. Print-out of variables
NPRINT=LSWEEP
GROUP 22. Spot-value print-out
IXMON=3*NX/4
GROUP 23. Field print-out and plot control
NPLT=5; IPLTF=2; IPLTL=LSWEEP
NROWCO=40; ORSIZ=0.4
PATCH(LONGPLOT,PROFIL,1,NX,1,1,1,1,1,LSTEP)
COVAL(LONGPLOT,MIXF,0.0,1.0)
COVAL(LONGPLOT,OXID,0.0,1.0)
COVAL(LONGPLOT,PROD,0.0,1.0)
COVAL(LONGPLOT,FUEL,0.0,1.0)
PATCH(LONGPLT2,PROFIL,1,NX,1,1,1,1,1,LSTEP)
COVAL(LONGPLT2,TMP1,0.0,0.0)
COVAL(LONGPLT2,U1,0.0,0.0)
COVAL(LONGPLT2,P1,0.0,0.0)
*************************************** MFM data
#mfm
NFLR=1; NFLF= 20 ! 20 fluids, distinguished by mixture fraction
nflf=3
The population-defining attribute is "mixture fraction", ie mass
of material derived from the inlet stream containing fuel (and
oxidant) per unit mass of local mixture.
MFMMOD=SCRS ! activate calculation of fluid temperature and
! other quantities in gxmfm
SPEDAT( MFM, FFUIN, R, 1.0)
SPEDAT( MFM, TAIRIN, R, TOXID )
SPEDAT( MFM, TFUIN , R, TFUEL)
SPEDAT( MFM, TSTOIC, R, TSTOIC)
SPEDAT( MFM, FACST , R, FSTOI) ! i.e. tmp2a
SPEDAT( MFM, GASCON, R, 8314.)
SPEDAT( MFM, SPVLMX, R, 100.0)
SPEDAT( MFM, SPVLMN, R, 0.01 )
SPEDAT( MFM, SMOCON, R, 1.0)
SPEDAT( MFM, SMOEXP, R, 7.0 )
SPEDAT( MFM, SMOEXP, R, 0.01 ) ! use to nullify temperature effect
the micromixing constant: conmix
conrea is set to zero, as not being relevant to this case
CONMIX=5.0; CONREA=0.0
TEXT(MFM; 1dsmoke; conmix=:conmix:
TITLE
#mfm1
** Initial conditions
REAL(REALNFL,INIFL); REALNFL=:NFLUIDS:
FIINIT(RATE)=100.0
INIFL=1./REALNFL
DO II = 1,NFLUIDS
FIINIT(F:II:)=INIFL
RELAX(F:II:,LINRLX,0.25)
COVAL(OUTLET,F:II:,ONLYMS,SAME)
ENDDO
** Boundary conditions
Fuel inlet
COVAL(FUIN,F:NFLUIDS:,ONLYMS,1.0) ! only fluid 20 enters here
** Oxidant inlet
COVAL(AIRIN,F1,ONLYMS,1.0) ! only fluid 1 enters here
COVAL(AIRIN2,F1,ONLYMS,1.0) ! and here
RELAX(H1,FALSDT,10.0)
Solve for SMOM, ie smoke according to multi-fluid model,
and SMOS, ie smoke according to single-fluid model.
SOLVE(SMOM,SMOS)
FIINIT(SMOM)=0.0; FIINIT(SMOS)=0.0
COVAL(OUTLET,SMOM,ONLYMS,SAME); COVAL(OUTLET,SMOS,ONLYMS,SAME)
The patch called smoke activates the coding for smoke
generation according to both the single- and multi-fluid models
PATCH(SMOKE,PHASEM,1,NX,1,NY,1,NZ,1,LSTEP)
COVAL(SMOKE,SMOM,FIXFLU,GRND); COVAL(SMOKE,SMOS,FIXFLU,GRND)
STORE(TMPM,FRFM,OXDM,PRDM)
CHAR(NAMPROF) ! line-printer plots
ORSIZ=0.2
DO II=1,NFLUIDS
NAMPROF=FPROF:II:
PATCH(:NAMPROF:,PROFIL,1,NX,1,1,1,1,1,1)
COVAL(:NAMPROF:,F:II:,0.0,0.0)
ENDDO
TSTSWP=-1; UWATCH=T; USTEER=T; NYPRIN=1; RESFAC=1.E-3
distil=t
expected values
EX(P1 )= 1.425E+04; EX(P1 )= 3.786E+04
EX(U1 )= 4.948E+01; EX(U1 )= 7.707E+01
EX(H1 )= 6.590E+06; EX(H1 )= 9.408E+06
EX(PRDM)= 4.451E-01; EX(PRDM)= 3.831E-01
; EX(OXDM)= 4.773E-01
EX(FRFM)= 8.193E-02; EX(FRFM)= 1.397E-01
EX(TMPM)= 1.580E+03; EX(TMPM)= 1.460E+03
EX(SMOS)= 4.530E-04; EX(SMOS)= 3.547E-04
EX(SMOM)= 2.564E-04; EX(SMOM)= 1.579E-04
; EX(F1 )= 4.727E-01
EX(F2 )= 1.867E-01; EX(F2 )= 1.142E-01
EX(F3 )= 1.088E-01; EX(F3 )= 7.434E-02
EX(F4 )= 6.151E-02; EX(F4 )= 5.543E-02
EX(F5 )= 3.851E-02; EX(F5 )= 4.300E-02
EX(F6 )= 2.639E-02; EX(F6 )= 3.415E-02
EX(F7 )= 1.926E-02; EX(F7 )= 2.767E-02
EX(F8 )= 1.471E-02; EX(F8 )= 2.282E-02
EX(F9 )= 1.164E-02; EX(F9 )= 1.912E-02
EX(F10 )= 9.470E-03; EX(F10 )= 1.626E-02
EX(F11 )= 7.886E-03; EX(F11 )= 1.401E-02
EX(F12 )= 6.699E-03; EX(F12 )= 1.224E-02
EX(F13 )= 5.791E-03; EX(F13 )= 1.083E-02
EX(F14 )= 5.090E-03; EX(F14 )= 9.705E-03
EX(F15 )= 4.548E-03; EX(F15 )= 8.832E-03
EX(F16 )= 4.138E-03; EX(F16 )= 8.191E-03
EX(F17 )= 3.858E-03; EX(F17 )= 7.813E-03
EX(F18 )= 3.762E-03; EX(F18 )= 7.901E-03
EX(F19 )= 4.392E-03; EX(F19 )= 1.022E-02
EX(F20 )= 1.133E-02; EX(F20 )= 3.056E-02
EX(MNSQ)= 1.137E-01; EX(MNSQ)= 1.773E-01
EX(AVEF)= 1.108E-01; EX(AVEF)= 1.683E-01
EX(RHO1)= 2.099E-01; EX(RHO1)= 2.311E-01
EX(PROD)= 6.985E-01; EX(PROD)= 6.835E-01
EX(OXID)= 2.289E-01; EX(SPH1)= 1.500E+03
EX(MIXF)= 1.108E-01; EX(MIXF)= 1.683E-01
EX(FUEL)= 7.253E-02; EX(FUEL)= 1.309E-01
EX(TMP1)= 1.997E+03; EX(OXID)= 1.856E-01
EX(RATE)= 1.000E+02
lsweep=500
STOP