Error specify vent orientation.

Info Fire Prevention

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Oct 10, 2014, 6:52:11 PM10/10/14

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I am trying to modify an existing FDS file I have and when I move the vent for the fire – I obtain an error message relating to the vent orientation.

I have checked the users manual and ensured that there is not a solid through the vent; altered the grid size and used IOR=3 which removes the error however results in no smoke or heat production.

Can anyone comment or refer me to a specific point in the users guide?

I have copied my code.

&HEAD CHID='Newton Grange 20 '/

&MESH IJK=300,20,24,XB=4,34,5,7.0,0,2.4/Mesh 3 Corridor 1

&MESH IJK=20,15,12,XB=30,34,7,10.0,0,2.4/Mesh 4 Stair 1

&MESH IJK=25,30,24,XB=11,16,-2,4,0,2.4/Mesh 1 Flat

&MESH IJK=20,19,12,XB=16,18,-14,5,0,2.4/Mesh 5 Corridor 2

&MESH IJK=07,3,12,XB=11,18,-17,-14,0,2.4/mesh 6 stair 3

&TIME TWFIN=600/

&VENT MB='XMIN', SURF_ID='OPEN' /

&VENT MB='XMAX', SURF_ID='OPEN' /

&VENT MB='YMIN', SURF_ID='OPEN' /

&VENT MB='YMAX', SURF_ID='OPEN' /

&OBST XB=30,34,9.9,10,0,2.4/north stair walls

&OBST XB=30,30.1,7,10,0,2.4/ west stair wall

&OBST XB=33.9,34.0,7,10,0,2.4/ east stair wall

&OBST XB=30,33.2,7.0,7.2,0,2.4/ south stair wall

&OBST XB=30,34,7,10,2.3,2.4,COLOR='INVISIBLE'/

&HOLE XB=31.5,32.5,8,9,2.2,2.5,COLOR='GREEN',DEVC_ID='TM1'/STAIR AOV

&OBST XB=16,17.2,-14,-13.8,0,2.4,/smoke control screen corridor 2 & stair 3

&OBST XB=16,18,-14,-13.8,2.0,2.4/smoke control screen

&OBST XB=17.2,18,-14,-13.8,0.0,2.0,COLOR='BLUE',/ CTRL_ID='cycling timer'

&HOLE XB=17.4,17.6,-14.2,13.6,1.2,1.4,/

&OBST XB=16,17.2,4.9,5.1,0,2.4,/smoke control screen corridor 2 & stair 3

&OBST XB=16,18,4.9,5.1,2.0,2.4/smoke control screen

&OBST XB=17.2,18,4.9,5.1,0.0,2.0,COLOR='BLUE',/ CTRL_ID='cycling timer'

&HOLE XB=17.4,17.6,4.9,5.1,1.2,1.4,/

&OBST XB=11,18,-17,-14,2.3,2.4,COLOR='INVISIBLE'/stair 3 roof slab

&HOLE XB=14,15,-16,-15,2.2,2.5,COLOR='GREEN',DEVC_ID='TM1'/STAIR 3 AOV

&OBST XB=33.2,34.0,7.0,7.2,0.0,2.0,COLOR='BLUE',CTRL_ID='cycling timer'/stair1 smoke control

&OBST XB=33.2,34,7.0,7.2,2.0,2.4/north stair well above door

&HOLE XB=33.6,33.8,6.8,7.4,1.2,1.4,/

&OBST XB=11.0,11.1,-2,4,0,2.4,COLOR='INVISIBLE',/apartment wall W

&OBST XB=11,16,-2,-2.1,0.0,2.4,COLOR='INVISIBLE',/ apartment wall S

&HOLE XB=10.8,11.2,-1.5,-0.5,1.0,2.2,COLOR='GREEN',DEVC_ID='TM2'/WINDOW BREAKAGE

&OBST XB=15.9,16.0,-2,4,0,2.4,/apartment wall E

&OBST XB=11,16,-3.9,4,0,2.4,COLOR='INVISIBLE'/apartment wall N

&OBST XB=14.8,15.0,5,5.2,0,2.4,COLOR='INVISIBLE'/apartment wall N

OBST XB=11,16,-2,4,2.3,2.4,COLOR='INVISIBLE'/

&HOLE XB=10.8,11.2,1.0,1.4,0.1,0.3/leakage into room of origin

OBST XB=0,34,-17,7,2.3,2.4,COLOR='INVISIBLE'/Roof slab

&OBST XB=4,34,7.0,7.1,0,2.4,COLOR='INVISIBLE',/corridor wall N

&OBST XB=5.8,34,5,5.1,0,2.4,COLOR='INVISIBLE',/corridor wall S

&OBST XB=33.9,34,5.2,7,0,2.4,COLOR='INVISIBLE',/corridor wall E

&OBST XB=4.0,4.2,5.2,7,0.0,2.4/corridor end walL w

&HOLE XB=13,13.4,6.9,7.2,1,1.4/corridor leakage corridor 1

&HOLE XB=25,25.4,6.9,7.2,1,1.4/corridor leakage corridor 5

&HOLE XB=17.8,18.2,2,2.3,1,1.4/corridor leakage corridor 2

&OBST XB=14.0,14.2,2.0,4.0,0.0,2.4,/flat 1 wall

&OBST XB=14,16,2,2.1,0.0,2.4/flat 1 2nd wall

&HOLE XB=14.8,15.4,1.9,2.2,0,1.8,COLOR='GREEN'/door open into internal hallway

&HOLE XB=15.8,16.2,3.6,3.7,0.0,2.0,/ Door from apartment into corridor

&OBST XB=15.9,16.1,3.6,3.8,0.0,2.4,COLOR='PURPLE',/

&OBST XB=20.8,21.0,5.2,5.7,0.0,2.4,/smoke control screen corridor 1 & 5

&OBST XB=20.8,21.0,6.5,7,0.0,2.4,/smoke control screen

&OBST XB=20.8,21.0,5.7,6.5,2.0,2.4,/smoke control screen

&OBST XB=20.7,21.2,5.7,6.5,0.0,2.0,COLOR='BLUE',CTRL_ID='cycling timer'/

&HOLE XB=20.6,21.4,6.0,6.2,1.2,1.4,/

&OBST XB=27.8,28.0,5.2,5.7,0.0,2.4,/smoke control screen corridor 5 & Stair 1

&OBST XB=27.8,28.0,6.5,7,0.0,2.4,/smoke control screen

&OBST XB=27.8,28.0,5.7,6.5,2.0,2.4,/smoke control screen

&OBST XB=27.7,28.2,5.7,6.5,0.0,2.0,COLOR='BLUE',CTRL_ID='cycling timer'/

&HOLE XB=27.6,28.4,6.0,6.2,1.2,1.4,/

&HOLE XB=15,15.9,4.6,5.4,1.0,2.4,COLOR='GREEN',DEVC_ID='TM1'/air inlet for extract system

&OBST XB=15.9,16.1,3.0,3.6,0.0,2.4,COLOR='BLUE',CTRL_ID='cycling timer',/door into flat 1

&DEVC ID='TIMER',XYZ=12,2,0,QUANTITY='TIME'/

&CTRL ID='cycling timer',FUNCTION_TYPE='CUSTOM', INPUT_ID='TIMER',RAMP_ID='cycle',/

&RAMP ID='cycle',T=0,F=1/

&RAMP ID='cycle',T=300,F=0/

&RAMP ID='cycle',T=390,F=0/

&RAMP ID='cycle',T=391,F=1/

&REAC ID='POLYURETHANE',SOOT_YIELD=0.07,N=1.0,C=6.3,H=7.1,O=2.1/

&PART ID='TRACER', MASSLESS=.TRUE./

&SURF ID='BURNER',HRRPUA=500.,PART_ID='TRACER',RAMP_Q='MEDIUM'/

&OBST XB=11.6,12.6,1,2,0.0,0.4,COLOR='YELLOW'/sofa fire

&VENT XB=11.6,12.6,1,2,0.4,0.4,SURF_ID='BURNER',COLOR='RED',/fire located in living area

&RAMP ID='MEDIUM',T=0,F=0/

&RAMP ID='MEDIUM',T=10,F=0.001/

&RAMP ID='MEDIUM',T=50,F=0.03/

&RAMP ID='MEDIUM',T=100,F=0.12/

&RAMP ID='MEDIUM',T=150,F=0.270/

&RAMP ID='MEDIUM',T=200,F=0.480/

&RAMP ID='MEDIUM',T=300,F=1.0/

&RAMP ID='MEDIUM',T=900,F=1.00/

&SURF ID='EXTRACT',VOLUME_FLOW=7.0,RAMP_Q='FAN',/

&VENT XB=4.4,5.0,5.8,6.6,2.4,2.4,COLOR='GREEN',DEVC_ID='TM1',SURF_ID='EXTRACT'/

&DEVC ID='TM1',XYZ=12,2,0,QUANTITY='TIME',SETPOINT=240,INITIAL_STATE=.FALSE./

&RAMP ID='FAN',T=0,F=0/

&RAMP ID='FAN',T=240,F=0/

&RAMP ID='FAN',T=250,F=1.00/

&RAMP ID='FAN',T=900,F=1.00/

&DEVC ID='TM2',XYZ=12,2,0,QUANTITY='TIME',SETPOINT=340,INITIAL_STATE=.FALSE./

&HOLE XB=11.2,11.6,-0.1,0.1,2.0,2.3,COLOR='BLUE'/

&HOLE XB=32,33,5.8,6.8,2.2,2.5,COLOR='GREEN',DEVC_ID='TM1',/

&TAIL/

dr_jfloyd

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Oct 11, 2014, 11:45:03 AM10/11/14

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Carefully check your input file. You have a lot of invisible obstacles. You have probably defined one with the wrong coordinates.

MS17

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Jul 21, 2017, 6:30:49 AM7/21/17

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&HEAD CHID='jet_fan'

TITLE='How to construct a simple jet fan'

/

&TIME T_END=30.0

/

&REAC FUEL='PROPANE'

SOOT_YIELD=0.100

/

! --- Free text: 'HEAD free text.1'

&HVAC ID='IN',TYPE_ID='NODE',DUCT_ID='JET FAN',VENT_ID='IN'/

&HVAC ID='OUT',TYPE_ID='NODE',DUCT_ID='JET FAN',VENT_ID='OUT'/

&HVAC ID='JET FAN',TYPE_ID='DUCT',NODE_ID='IN','OUT',VOLUME_FLOW=-1.0,AREA=0.2/

! --- Boundary conditions (from Blender Materials)

&SURF ID='FIRE'

RGB=255,255,0

HRRPUA=700.0

/

&MESH ID='Cube'

IJK=50,50,50

XB=0.165,10.195,-2.020,1.848,-0.241,3.721

/

! --- Geometric entities (from Blender Objects)

! 2 faces

&VENT ID='F1_1'

XB=2.699,2.699,-0.297,-0.127,1.400,1.556,SURF_ID='HVAC',ID='IN',COLOR='RED'

/

! 2 faces

&VENT ID='F2_1'

XB=2.499,2.499,-0.297,-0.127,1.400,1.556,SURF_ID='HVAC',ID='OUT',COLOR='GREEN'

/

&OBST ID='New OBST'

XB=2.499,2.699,-0.297,-0.127,1.400,1.556

COLOR='YELLOW'

/

&OBST ID='New OBST.001'

XB=5.200,5.600,-0.200,0.200,0.000,0.200

SURF_IDS='FIRE','INERT','INERT'

/

&HOLE ID='Plane'

XB=10.175,10.196,-0.938,1.083,1.376,2.794

/

&OBST ID='Plane.001'

XB=0.182,10.241,-2.021,1.833,-0.181,3.717

/

&VENT MB='XMIN', SURF_ID='OPEN' /

&VENT MB='XMAX', SURF_ID='OPEN' /

&TAIL /

! Generated in 0 s.

This is my code and i am facing the same error how can i rectify it

Thanks in advance

fde

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Jul 21, 2017, 7:33:46 AM7/21/17

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You should remove the last &OBST. It is a big obstruction that fills the whole mesh. Does not have any function.

MS17

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Jul 24, 2017, 6:28:36 AM7/24/17

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why am facing this error again anfd again

&HEAD CHID='jet_fan'
TITLE='How to construct a simple jet fan'
/
&TIME T_END=30.0
/
&REAC FUEL='PROPANE'
SOOT_YIELD=0.100
/

! --- Free text: 'HEAD free text.1'

&HVAC ID='IN',TYPE_ID='NODE',DUCT_ID='JET FAN',VENT_ID='IN'/
&HVAC ID='OUT',TYPE_ID='NODE',DUCT_ID='JET FAN',VENT_ID='OUT'/

&HVAC ID='JET FAN',TYPE_ID='DUCT',NODE_ID='IN','OUT',VOLUME_FLOW=-6.0,AREA=0.04/

! --- Boundary conditions (from Blender Materials)

&SURF ID='FIRE'
RGB=255,255,0

HRRPUA=1000.0

/

! --- Geometric entities (from Blender Objects)

! 125000 mesh cells of size 0.488x0.300x0.082 m
! Max cell aspect ratio is 6.0
&MESH ID='New MESH'
IJK=50,50,50
XB=-5.615,18.799,-10.499,4.500,-0.001,4.080
/

&HOLE ID='Cube'
XB=-5.623,-5.586,-0.193,0.715,1.869,2.488
/

&HOLE ID='Cube.001'
XB=9.515,10.579,3.017,3.112,2.537,3.558
/

&VENT XB=4.199,4.199,-0.200,0.200,1.400,1.800,SURF_ID='OPEN',SURF_ID='HVAC',ID='IN',COLOR='RED'
/

&OBST XB=4.000,4.200,-0.200,0.200,1.400,1.800
/

&OBST ID='New OBST.005'
XB=5.200,5.600,-0.200,0.200,0.000,0.200
SURF_ID='FIRE'
/

&VENT XB=3.999,3.999,-0.200,0.200,1.400,1.800,SURF_ID='OPEN',SURF_ID='HVAC',ID='OUT',COLOR='BLUE'
/

&TAIL /
! Generated in 0 s.

This is my code and i am facing the same error again how can i rectify it

Thanks in advance

fde

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Jul 24, 2017, 7:15:25 AM7/24/17

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The size of your &OBSTruction is smaller than the grid size. Adjust the obstruction and update the vent locations accordingly please.

MS17

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Jul 24, 2017, 7:53:04 AM7/24/17

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Thank you fde i was able to find the error and rectify it properly

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