Wall temperature in MFix

Say in a 2D TFM simulation of rectangular domain, I apply heat flux on the right side wall. How do I calc the wall temperature in that simulation?
Another question is how exactly is the heat flux applied? What is the formulation. I tried to look a lot into the MFix documentation but it is not clear. I am applying the gradient in K/m to each phase separately…does this mean the total wall heat flux is kf*(dTg/dx) + ks*(dTs/dx) ?

Help from the MFix team is appreciated