Are you trying to simulate the tank filling with a time-dependant problem? How did you set up your geometry and boundary conditions? I'm curious if you tried to set this up as closed system, modeling both tanks and pipes (this would not give you a good answer).
- I did try simulating it as a time-dependent problem, but that worked out worse than time-independent since I was getting a higher pressure drop.
- The geometry of the boundary is there's a small circular hole on the outside of each tank, for the inlet and outlet. The first hole (on first tank) was set up to be the inlet with volume flow of around 2000 in3/s. The second hole (on second tank) was set up to be the outlet with environmental pressure.
I did try setting this up as a closed, singular system with the tanks and pipes included. Why would this not work? Would the solution then be as simple as adding up the pressure drops across each individual component?
I'm not sure I understand, maybe a diagram or a screenshot would be better.
If I get what you're saying, you have water from the environment coming into tank A, going through a pipe into tank B, and then leaving back to the environment?