COMSOL simulation for heat and mass transfer across membrane for membrane distillation process

Hi,
For your information, I am developing a COMSOL simulation for the direct contact membrane distillation (DCMD) process. It is actually a process which involve the heat and mass transfer from the bottom cell (hot feed side) across the membrane (porous medium) and reach the upper cell (cold permeate side).

upper cell (hot feed side) --> heat convection
membrane (hydrophobic) --> heat convection (water evaporation) + heat conduction in membrane
lower cell (cold permeate side) --> heat convection (vapor condense back to water)

I am currently using 2 physics which are conjugate heat transfer + free and porous media flow.
I was able to simulate the convective heat transfer at the upper and lower cell + heat conduction in membrane matrix. However, no mass flux was flowing across the membrane, which means no heat convection was developed within the membrane.

Thus I would like to ask is it possible to simulate the heat convection through membrane together with the flows at the cells? How do I link the three layers together so that there is fluid flowing from the bottom to the upper side?

Thanks for your time and wish you have a good day.

Patricia