[alextau]

Hello,

I am trying to solve a problem similar to severe sluging. It a U shaped pipe which is partially filled with water at the lower section. At the inlet, I use the fixedValue type as a velocity bc. The outlet should be open to atmosphere.
I am very confused about setting the p and the p_rgh conditions for the outlet. I understand that the code solve NS equations for p_rgh and further calculates p for using as state equation to corect the density. If I am right, that means that I should set p_rgh to atmospheric pressure 101325 Pa. However p_rgh is the static pressure minus the hydrostatic pressure (which depends on the coordinates system)...

Can you please help me to understand what should I do in order to fix the oulet to atmospheric pressure of 101325 Pa?

A.