Reservoir simulation
 

i am trying to simulate a reservoir system with some mass in mass out. i have full mouth flow at inlet and outlet. i am going for a multiphase VOF model to see the air water interface in the model. I have following doubts:
1. do in need to go for open channel flow VOF model?
2. the reservoir is closed from the top, so do i need to give open to atmosphere BC at the top wall or wall boundary condition will do?
3. I have information about fixed mass flow rates at inlet and outlet, what kind of BC at inlet and outlet i can go for? currently i am going for massflow inlet and pressure outlet..
4. i am using air as secondary phase and water primary phase. is it correct?

i am using now open channel flow BC at outlet as i observed due to elongated outlet the outlet is no longer remaining fullmouth flow. now i am using open chennel flow and giving water height at the outlet. i must see a positive change in the behavior :rolleyes:.

will it be good to use eulerian model in stead of VOF..but i want to see interface also. any help or suggestion....