How to monitor the lift and drag of the porous block in flow?
 

I want to know the lift and drag when flow past a porous plate. The plate is set to be porous media and the outline of it is set to be interface...However, when I try to monitor the lift of this plate, I found I cannot and it is only for the 'wall' boundary condition.
So how can I get the Cl and Cd (or lift and drag) of this plate?

Hi,SNeCu
I also confuse about this problem. Did you find the solution ?