[Starcatcher]

Hi,
ich am simulating a simple 2d-pipe mit a nozzle as a test for later combustion chamber.

k-epsilon, methane, no ractions, very good cell quality, ideal gas

I always get good convergences (with different turb.models, pressuren, etc.) except of if I set the heat capacity (cp) from constant to "kinetic law". Then i get fluctuations in the residuals, the mass-flow. I guess it comes from the nozzle-reagion.

Does anybody have experience with this setting? What could be the reason?
Thanks

Pictures: after the 60th iteration i switched to "kinetic theory" for cp

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