[Audrius]

Hello colleagues,

I would like to perform Fluent validation for natural circulation phenomena with conjugate heat transfer. For the beginning, I created a simple geometry, which consists of two parts: fluid and solid zones. In the bottom part of fluid zone there is water, in the top there is air. The solid part is made from aluminium. After first iteration I noticed, that density of aluminium plate is not the same throughout the solid plate. In the outside of aluminium plate the density is 0 kg/m3. This should not be. When I use the same geometry, the same mesh for single flow, for example, the density of plate is good. I do not understand why what is. I think it's related to the VOF model.

Maybe You can explain where I am doing mistake, please?

[LuckyTran]

Check the boundary conditions for the aluminum and see if you specified a funny phase. The "density" is the bulk density which is the sum of phase-densities.

In multi-phase problems, it's always a good idea to have a plot of the phase fractions.

[Audrius]

Here presented properties of aluminium:


Air density:


Air volume fraction:


Water density:


Water volume fraction:


And here is density contour in Fluent:


Why in the Fluent I see good density, but in CFD-Post with changes?

[mcuneytk]

hi;
did you find the solution ?
I have similar problem. I created a solid zone for wall and after initialization, I see that density of solid zone is zero even I entered constant value in materials section.
Fluid zone looks ok.

Originally Posted by LuckyTran

Check the boundary conditions for the aluminum and see if you specified a funny phase. The "density" is the bulk density which is the sum of phase-densities.

In multi-phase problems, it's always a good idea to have a plot of the phase fractions.