Simple heat exchanger
 

Hello, I want to simulate simple countercurrent heat exchanger but I don't have idea how to define outlets? If I choose pressure outlet for the both outlets (hot and cold current) in the Physics values I have to specify Static temperature but I don't want to specify outlet temperatures - I want program to calculate those temperatures for me. And of course if a specify those temperatures in the outlet (pressure outlet-physics values) it gives me completely different solutions for every different temp. So what should I choose for the outlets? Thanks in advance, Strahinja

Ok, I get it out. I will explain if someone else have this problem. I just followed simulation developing and saw that between each iteration it says: Air outlet:reversed flow on 8 faces. Then I turned on mesh for scalar scene (temperature) and saw that exactly 8 faces have temp. that I specified under air outlet(pressure outlet)-physics values-static temperature. All other cells had good temperatures-totaly different than that specified for pressure outlet boundary (which I named air outlet). In other words, temperature that is specified for pressure outlet boundary only counts if reversed flow accour. Number of reversed flows decrease as number of iterations increase - cenvergence. So just wait for all curves to convergate, don't be unpatient as I was and all reversed flows will disappear.