Vof oulet bc with gravity
 

I was running a problem using VOF with gravity turned on (interFoam and rasInterFoam). Using the damBreak case as an example, if the gravity is reversed, the liquid is supposed to flow out of the top boundary (atmosphere). Using the default boundary settings (pressureInletOuletVelocity for U and totalPressure for pd). I found that a good portion of the liquid was bounced back to the domain. However, if the gravity was turned off at some point in time (say, 0.2 s), the liquid will flow out of the domain naturally. In contrast, Fluent can handle this pretty well with pressure outlet bc. I tried several different combinations of BCs for U and pd, but without luck. Does anyone have a solution for this or knows what's going on with OpenFOAM's VOF BC implementation?

I am working with the damBreak tutorial and I am using Fluent as a postprocessor. The problem is that I don't know how to see the volume fraction in Fluent.
Does anybody know how to do it?

Thanks in advance

I just answered this in another thread. Nevertheless. You hit point 5 and 7 of http://openfoamwiki.net/index.php/Ho..._Message_Board

Bernhard