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Old   October 13, 2014, 03:03
Default H-Energy Imbalance
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Marcin
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Hello,
I have question about imbalance values.
Can anyone interpretate H-Energy Imbalance values.
Thats values are ok or not ??
Best regards
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Old   October 13, 2014, 05:18
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It depends on what you are trying to do. So do a sensitivity study and work it out for your case - converge to a imbalance level and record the parameters of importance to you. The converge to 10x tighter imbalance level and see the change in the parameters. If the change is small enough that you are happy with the variation then you have converged tight enough. If you are not happy with it then go 10x tighter again and repeat until you are happy.
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Old   October 13, 2014, 06:06
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Looking at those imbalances I'd make a punt and say you need to increase the physical time step of your energy equation.
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Old   October 13, 2014, 06:11
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On closer look I note the H imbalance is about 70%. That means you are likely to be miles away from convergence. It is pretty unlikely you have a usable result with convergence this poor.
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Old   October 13, 2014, 07:51
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I find my mistake
That was in boundary conditions.
I define mass flow on inlet and outlet. So I change to average static pressure with relative pressure 0 Pa on outlet and now it converge
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