[Hexahedron]

I have the following problem for which I have found no solution so far.

I have a porous media zone surrounded by solid regions. There is a heat source on one side of the solid regions and so heat is conducted through the solid to the interface between the solid region and the porous media.

Now as I'm using the non-equilibrium thermal model in the porous zone, there are separate energy equations for the fluid and solid in the porous medium, which are coupled together through convective heat transfer. Also, Fluent creates a wall and its shadow interface between the solid region and the porous fluid for which heat transfer is coupled.

As There is a separate energy equation for the porous solid, a third interface is also created between the porous solid and the solid region. However options for this interface are the same as for boundary walls, meaning that by default heat flux is set to zero so that there is no direct heat transfer between the solid region and the porous solid. There is also no obvious way to couple the porous solid with the solid region at the interface.

Now since I have temperatures of over 1000 degrees Celsius, heat transfer from the solid region to the porous solid due to radiation would be significant. Currently, with only the porous fluid energy equation coupled with the solid region the results are poor as the heat transfer from solid to porous solid is not accounted for. As such, the non-equilibrium thermal model seems pretty useless to me.

Has anyone come across the same problem or have idea of how to properly couple heat transfer at the solid and porous solid interface, possibly with UDFs?