Sorry Rob what do you mean by ” Check how the solid interacts with the fluid walls (it doesn’t) before deciding if you should use it. “?

When the fluid passes through porous medium, wont be any thermal interaction between them?

Lets say there is an enclosure filled with solid spherical particles and some space is empty and open for fluid to pass, when fluid (in this case a gas with higher temp than spheres) passes through, they exchange heat right? Is this Heat Transfer Coefficient for that interaction? or I am getting something wrong about porous zone modeling?


I found a paper on heat transfer in packed beds which addresses Furnas equation in Kitaev's book (attached image), but seems they are mostly based on experimental data for limited material and flow velocities and I am in doubt if they would be applicable for modelling soil as packed bed.