I am trying to model natural convection in a closed model, and I want to use Boussinesq approximation, my Ra number is 10e10, my question is, where to specify the thermal expansion coefficient, because the manual says specify it in the material panel after you specify the density, but I was not able to find it or find any place to add it. my second question is do you have any recommendations how to attack this problem with this high Ra number, which is going to be turbulent, can you please provide some details for the solution procedure. Thanks

if you change in the material panel the density to Boussinesq, then the panel updates and if you scroll with the scrollbar down, there must appear the thermal expansion coefficient. i hope this helps so far.

If you are looking for convection induced by heat conduction, recently a few papers were published by Tan Ka Kheng. you can search his aper in sciencedirect. I think got one paper where he is using fluent to simulate the natural convection in porous media