How to compute transport coefficients in faces ??

Asghari

Hi ;

In CFD packages and finite volume method we need to transport coeficients in faces ( regarding of integration on faces )for example for energy equation we want conductivity in face instead of cell.

we know value of conductivity in cells ; How can we access to transport coefficients in faces from as value as in cells?

Also i want to know how this work is done for two-phase flows.

I am appreciated for everybody to help me in finding answer to this questions.

Thanks a lot.