Oil flow closed chamber
 

Hi,
Thank you in advance, I’m new to the forum.

I have an axial symmetric model in Fluent of a cylindrical chamber full of oil which has a tube (with power generation) in its center. The oil of the chamber can flow outside and inside the tube for natural convection. Boundary convection conditions are applied to the chamber external walls.gravity is activated.

I want to study the cooling effect and the the temperature of the oil.

Which is the correct model to apply? Are there any particular setting?
I tried both laminar and k-omega models without reaching the convergence (continuity in particular). Energy model is applied.

I used the default methods settings.