mass imbalance at the inlet, interface, outlet
 

In my turbine simulation, there is some mass imbalance between the inlet, interface, and outlet. I have two domain: stator and rotor, connected by an interface. When i checked the mass flow through the interface, there was a huge difference (say 60 lps at inlet, 3 lps at the interface, and 58 lps at outlet). why is there very little mass flow through the interface, which should exactly the same 60 lps at all locations?
Thanks much.

I don't have turbo machinery experience so I'll talk in broad terms. The first and obvious question is have you properly defined your setup? Do the tutorials simulate turbo machinery problems the same way you are?

Secondly have your residuals reduced sufficiently?

Lastly, are your inlets and outlets far away from where the action occurs?

Thanks RicochetJ,. yes i checked the tutorials and did the setup in the same way as in tutorials...inlets and outlets are far way though..my redisudals reduced to 10-4 but not less than that...