Learning Forum

[Gearóid Farrell]

Hi, I am trying to use the non-equilibrium thermal model in ANSYS Fluent to study a conjugate heat transfer problem involving porous media. In my domain, I have an aluminum base layer, with a constant temperature applied to its bottom face. Above this, I have an aluminum porous region that will transfer heat to the fluid flowing over the system (see first image). 

I only created to bodies - the base layer and the porous region. When I activate the non-equilibrium thermal model, Fluent creates an additional "solid" body in the porous region to solve the solid energy equation. 

The final results however are not what we expect. The issue I am encountering is that heat is not being properly transferred between the base layer and the solid part of the porous region. You can see from the temperature plots that there is only heat transfer to the fluid near the top surface of the base layer, i.e. there is apparently no direct heat conduction from the base layer into the "solid" part of the porous region that Fluent created. We expected the temperature of the porous region to be uniformly higher, since the inlet velocity is fairly low. 

Maybe there is an issue with the interface between the base layer and the new "solid" part of the porous region?

I would greatly appreciate any help you could offer on this matter. Thank you! ????

[Rob]

Read the manual very carefully: the new solid representing the porous solid is only connected to the fluid region. It is not connected to the walls bounding the fluid region. 

[Gearóid Farrell]

Thanks for the reply. Sure, this is what I thought, but do you know of any way that I can thermally connect the top of the base layer to this "solid" region created by Fluent? Or do you think it is impossible?

[Rob]

It is possible using UDFs, or potentially expressions, but splitting the heat flux between the fluid and solid walls may not be overly straightforward. Start your reading with DEFINE_PROFILE, beyond that I can't offer much assistance.