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matt January 5, 2007 05:47

smoke (fire simulation)
 
hi everyone, I am trying to simulate a fire and instead of simulating combustion, i want to release smoke from a surface. However, i could not find physical properties (density, viscosity, etc.) of smoke. does anyone has a suggestion? My main problem is i dont have necessary hardware (such as enough ram) to simulate combustion nor release number of species (CO, CO2, H2O, soot etc.) from a surface. Instead I am trying to find out what would be the viscosity and density of a typical smoke. Instead of releasing 4-5 different species from a surface, i just want to release air and smoke mixture into air. Since it would be impossible to duplicate chemical combination of a car fire, anything close to it would be enough for me. I hope it is clear. thanx much

Riadh January 6, 2007 22:27

Re: smoke (fire simulation)
 
In the documentry of P{HOENICS (tr010-FAQ.doc)you can find your answers cocerning modelling fire and smoke in FLAIR using a blockage or an INLET.

I hope this helps.

Riadh

abdulkareem March 25, 2007 10:32

Re: smoke (fire simulation)
 
Simulator 5

Massimiliano Venturini October 1, 2007 03:15

Re: VENT problem (fire simulation)
 
I have some difficult whit FDS running. particulary I have difficult to write Vent properties in the VENT record. In the following I indicate the input that he has generated messages of error for record &VENT.

thank you Massimiliano

&HEAD CHID='prova_3', TITLE='Simulazione di prova' /

&MESH IJK=460,340,40, XB=0.0,46.0,0.0,34.0,0.0,4.0 /

&TIME TWFIN=18000., WALL_INCREMENT=1, DT=30 /

&MISC SURF_DEFAULT='CONCRETE', TMPA=25. /

&MATL ID = 'PLASTIC'

CONDUCTIVITY = 0.2

SPECIFIC_HEAT = 1.5

DENSITY = 1500.

N_REACTIONS = 1

HEAT_OF_REACTION = 3000.

HEAT_OF_COMBUSTION = 25000.

REFERENCE_TEMPERATURE = 400.

NU_FUEL = 1.0 /

&MATL ID = 'CONCRETE'

FYI = 'Quintiere, Fire Behavior'

SPECIFIC_HEAT = 0.88

DENSITY = 2100.

CONDUCTIVITY = 1.0 /

&SURF ID = 'PLASTIC'

MATL_ID = 'PLASTIC'

COLOR = 'BLUE'

BACKING = 'EXPOSED'

THICKNESS = 0.002 /

&SURF ID = 'CONCRETE'

COLOR = 'GRAY 60'

MATL_ID = 'CONCRETE'

THICKNESS = 0.3 /

&SURF ID = 'FIRE', HRRPUA=1000., RAMP_Q='fireramp', COLOR='RED' /

&OBST XB= 10.0, 15.0, 2.0, 5.0, 0.0, 2.0, SURF_ID='PLASTIC' / Materiale Combustibile &OBST XB= 5.0, 46.0, 16.0, 16.3, 0.0, 4.0, SURF_ID='CONCRETE' / Parete Interna &VENT XB= 10.0, 15.0, 2.0, 5.0, 2.0, 2.0, SURF_ID='FIRE', XYZ =13.0, 5.0, 2.0, SPREAD_RATE=0.03, ORIENTATION=3 /

&RAMP ID='fireramp', T= 0.0, F=0.0 / &RAMP ID='fireramp', T= 1.0, F=1.0 / &RAMP ID='fireramp', T= 30.0, F=1.0 / &RAMP ID='fireramp', T= 31.0, F=0.0 /

&VENT MB='ZMIN', SURF_ID='OPEN' / &VENT MB='ZMAX', SURF_ID='OPEN' /

&BNDF QUANTITY='WALL_TEMPERATURE' / &BNDF QUANTITY='BURNING_RATE' / &BNDF QUANTITY='HEAT_FLUX' /

&HOLE XB= 7.0, 9.0, 16.0, 16.3, 0.0, 2.0 / &HOLE XB= 15.0, 17.0, 16.0, 16.3, 0.0, 2.0 / &HOLE XB= 22.0, 24.0, 16.0, 16.3, 0.0, 2.0 /

&ZONE XB= 5.0, 40.0, 0.0, 16.0, 0.0, 3.4 / Pressure Zone 1 &SURF ID='BLOW', POROUS=.FALSE., VEL= 0.4, DUCT_PATH=2,1, MAX_PRESSURE=1000. /

&HOLE XB= 20.0, 20.4, 8.0, 8.4, 3.7, 4.0 / &OBST XB= 20.0, 20.4, 8.0, 8.4, 3.7, 4.0, COLOR='RED', SURF_ID='BLOW', PERMIT_HOLE=.FALSE. /

&SLCF PBZ=0.0,QUANTITY='TEMPERATURE',VECTOR=.TRUE. / &SLCF PBZ=0.0,QUANTITY='DENSITY' / &SLCF PBZ=0.0,QUANTITY='PRESSURE' / &SLCF PBZ=0.0, QUANTITY='HRRPUV' /

&BNDF QUANTITY='WALL_TEMPERATURE' / &BNDF QUANTITY='BURNING_RATE' /

&PROF XYZ=0.0,0.0,0.0, IOR= 3, QUANTITY='DENSITY', ID='Top Center Density' /

&PROF XYZ=0.0,0.0,0.0, IOR= 3, QUANTITY='PLASTIC', ID='Top Center Plastic' /

&PROF XYZ=0.0,0.0,0.0, IOR= 3, QUANTITY='TEMPERATURE', ID='Top Center Temp' / &PROF XYZ=0.0,0.0,0.0, IOR= 3, QUANTITY='BURNING_RATE', ID='burn' /

&TAIL /

hari October 23, 2007 01:40

Re: smoke (fire simulation)
 
dear matt, can u tell me how to model release of air and smoke mixture into air. Thanks in advance Hari V.B.


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