Learning Forum

[Punit2019]

Hello,

FLUENT uses a default formula, as follows, for calculating the effective thermal conductivity (Keff) of a porous medium, after the user enters the K values for the solid and fluid mediums (Ks and Kf respectively) and the value of porosity (Epsilon):

But this is actually the maximum effective thermal conductivity obtainable for the given inputs. The actual Keff must lie below the value obtained from the above formula. This is why I need to customize the formula using the same inputs. 

Is there a way to overwrite the default formula?

Can I use a custom field function for this purpose?

Any help would be appreciated.

 

Cheers.

[Rob]

There are a couple of options in the non-equilibrium approach, otherwise you'll need to adjust porosity itself to fudge the result. That can be altered via a UDF or (potentially) an expression depending on how complex the position v k_eff relationship is.