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Old   February 20, 2011, 15:50
Default natural convection ventilation
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Fabian Braennstroem
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Hi,

I am just trying to setup a small test case in 1.7.x for a generic HVAC case with two dummy cylinders placed in the room as a heat source with a heat flux boundary condition... I attached the case with the snappy mesh.
The meshing and running works fine... unfortunately there is no 'plume' development above the cylinder. The heat flux/power is set to 50W for the cylinder1 and it should give for this setup a velocity of around up to 0,2m/s at 40cm above the cylinder... I get something with 4e-5 m/s (just after 350 iterations, but this is still strange for me) !?
It is probably a quite stupid mistake, but I can't find it and would be happy, if one of you have a hint, what I am doing wrong with the setup!? I actually tried to upload the stl's as well, but they were a bit too large, so if someone needs them I would send it by mail.

Best Regards!
Fabian

Btw... the above counts for a relaxation factor of 1.0 for rho and not like in the fvSolution of 0.01 and the z-direction goes a long with the height of the room.
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File Type: gz 1Heated_Room_1Cylinder.tar.gz (13.0 KB, 31 views)
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Old   February 21, 2011, 03:37
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Fabian Braennstroem
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sorry bothering you, I was just not waiting long enough ;-)
After around 1500 iterations I could see that it goes in the right direction...
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Old   March 28, 2011, 09:59
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Luis Blanes
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Hello Fabian

Which solver do you use to run the Code?

Thanks
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Old   March 29, 2011, 14:03
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buoyantSimpleFoam
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