I'm trying to do a flow simulation on a closed loop system. Until now, I had worked with open systems to get used with flow simulations.
For this simulation, the inputs are what in an open system would be the outputs: outputs and inputs are the same. I guess that I should define some initial conditions of the fluid (temperature, mass flow,...), but I don't know how to define that given that for this problem I don't have "Lids" as I use to have.
I'll start with a simulation without gravity, and once I know how to do this simulations I'll include gravity and apply a difference of pressure between A and B (see picture)
There is a picture for doing this question more understandable: