I am simulating the flow through a plate hx and coming across some problems. I believe my problems stem from not knowing how to properly apply fluid subdomains and boundary conditions. I have been able to run flow simulation and view my results, but I am coming across imposible conditions ( velocity of 0, temperatures falling to -400 F when my initial temperatures are in the range of 70 F to 900 F, and vaccuums when applying pressures).
My two fluids are both air. I have included two subdomains: hot air and cold air.
For both of them, I entered the flow velocity along with the pressure and temp.
I have four boundary conditions: cold in, cold out, hot in, hot out.
For both of my inlets I defined the boundary condition as a pressure opening defining the temperature and pressure.
For both of my outlets I defined the boundary condition as a flow opening defing the outlet mass flow rate.
The reason I set up the boundary conditions this way is because I don't know the outlet parameters.
I am new to flow simulation, so I may be missing what might seem to be obvious.