Hello,

I have the following case: a tank (initially filled by air) is underwater, at t=0 water enters through an opening. It is the only opening air goes out thought the same area. What kind of boundary can I use? Will a pressure inlet handle air going out?

Regards,

Nico

i think you can pressure outlet Bc, since it allows in and out depends on preesure. where as incase of pressure inlet it is forcing the fluid to go in... i hope you got it..