[musahossein]

Originally Posted by akidess

I would sample alpha and p along the walls, and use a python script to filter out values you don't want.

Good suggestion. But I see a potential problem though:

Say my phases are 0 and 1. So I know the interface or free surface occurs at 0.5. I can find out using sampleDict what the phase values are along the vertical surface. The accuracy of the phase value will depend on how many points I sample the phase along the wall vertically. So if I have 40 cells in the vertical direction, then I must sample the phase at more than 40 points - say 60 points. Now I will need to compute where the phase transition ("0.5") occurs and correlate that with all the points the pressures are measured. So there will have to be two sets of interpolation:
1. Find where 0.5 phase occurs and record the height
2. Find the corresponding height in the pressure value file. Interpolate between the values in the event there is no exact match.

Too bad OpenFOAM does not have this utility. An unfortunately I am not great at C++