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Boussinesq model gives constant density

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Old   February 6, 2008, 08:51
Default Boussinesq model gives constant density
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I'm using the Boussinesq model for density for a natural convection problem with water. I've set the operating temperature and thermal expansion coefficient for water.

The temperature difference is a maximum of 25K but still the density contours are constant throughout the entire domain. However I do get a velocity field and the only driving force I have is buoyancy so there must be some density difference. Why can't I see it in reports or contours?

Regards Ola
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Old   February 13, 2008, 04:30
Default Re: Boussinesq model gives constant density
S. Gatzka
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The Boussinesq-Approximation is applyed just to the buoyancy-expression in the navier-stokes-equations and not to the general density, which is treated as constant.

I experienced the same problem with a natural convection problem. The density was constant all over the area. But I got the right solution for the velocity-field. Therefore I suppose there is an other problem with your simulation.
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Old   February 21, 2008, 08:51
Default Re: Boussinesq model gives constant density
Necmi Cevheri
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If you did not use a boundary layer in the vicinity of a wall, you may not observe those density gradients. Try meshing with a boundary layer in gambit
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