SMV view of gravity vector

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fde

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Apr 5, 2019, 11:10:47 AM4/5/19
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The example file of the code given in User guide 7.4 Gravity gives an outlook in SMV as below. I do not understand why g vector is so off from z. Could you please explain?
Thank you
Capture.JPG

fde

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Apr 5, 2019, 11:11:29 AM4/5/19
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&HEAD CHID='V1'/
&TIME T_END=0.0/

&MESH ID='Mesh01', IJK=100,10,10 XB=0,100,0,10,0,10/


&MISC GVEC=1.,0.,1., RAMP_GX='x-ramp', RAMP_GZ='z-ramp' /
&RAMP ID='x-ramp', X= 0., F=0.0 /
&RAMP ID='x-ramp', X= 50., F=0.0 /
&RAMP ID='x-ramp', X= 51., F=-0.49 /
&RAMP ID='x-ramp', X=100., F=-0.49 /
&RAMP ID='z-ramp', X= 0., F=-9.81 /
&RAMP ID='z-ramp', X= 50., F=-9.81 /
&RAMP ID='z-ramp', X= 51., F=-9.80 /
&RAMP ID='z-ramp', X=100., F=-9.80 /

&TAIL /

Glenn Forney

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Apr 5, 2019, 9:36:59 PM4/5/19
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Z vector normally points up. G vector normally points in negative z direction ie down. In an fds input file you can define G to point in an arbitrary direction allowing you to simulate a hall that slopes. I don't have access to the example you are referring to but imagine it is an example of simulating a sloped compartment

On Fri, Apr 5, 2019, 11:10 AM fde <yilmaz....@gmail.com> wrote:
The example file of the code given in User guide 7.4 Gravity gives an outlook in SMV as below. I do not understand why g vector is so off from z. Could you please explain?
Thank you

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fde

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Apr 7, 2019, 6:59:09 AM4/7/19
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I understand that slope is shown in SMV and g is always down but in the example above (second post) slope is a rather small angle. However in SMV it is represented in a much larger angle. That confused me.


On Saturday, April 6, 2019 at 3:36:59 AM UTC+2, Glenn Forney wrote:
Z vector normally points up. G vector normally points in negative z direction ie down. In an fds input file you can define G to point in an arbitrary direction allowing you to simulate a hall that slopes. I don't have access to the example you are referring to but imagine it is an example of simulating a sloped compartment

On Fri, Apr 5, 2019, 11:10 AM fde <yilmaz...@gmail.com> wrote:
The example file of the code given in User guide 7.4 Gravity gives an outlook in SMV as below. I do not understand why g vector is so off from z. Could you please explain?
Thank you

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dr_jfloyd

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Apr 7, 2019, 8:07:21 AM4/7/19
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We only write GVEC to the SMV file and the Smokeview doesn't know about the RAMP. On your MISC line GVEC=1,01 which matches the image you attached. If you want Smokeview to draw your geometry at something that resembles your average GVEC you could try:

&MISC GVEC=-0.245,-9.805/
Then for the x-ramp you would have F=2 and for the z-ramp you would have F=0.99949

fde

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Apr 8, 2019, 2:05:44 AM4/8/19
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That solves my issue. Thank you.
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