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Turbulence Model in axisymmetric nozzle simulation

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Old   May 21, 2013, 02:03
Default Turbulence Model in axisymmetric nozzle simulation
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Hi

I am simulating an axisymmetric nozzle. I have an issue with which turbulence model to use. Currently I am using standard K-epsilon and i am not getting any shock wave inside the nozzle. When I switch to SST K omega i get shock wave in the flow.

I would like to ask which is the recommended turbulence model for these type of flow
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Old   May 21, 2013, 05:27
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By intuition, std k-eps model is diffusive and hence may smear out the sharp gradients responsible for shocks. Have you tried realizable model? It is deemed to be good in modelling jets.

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Old   May 22, 2013, 11:50
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Yes, Just tried realizable.. it also shows a shock wave
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Old   September 4, 2017, 12:11
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Hi, could i ask you what do you mean by diffusive?
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Old   September 4, 2017, 16:57
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K-epsilon does not behave well in large pressure gradient, one like shocks, I'd suggest to stick with SST. By diffusive he means the behavior of the solver, like for eg:- Picks the information from the succeeding nodes and moves forward
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Old   September 4, 2017, 23:35
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I see that the SST k-omega model is more suitable for compressible flow into a nozzle for its good behaviour in adverse pressure gradients (shock) and separating flow. Thank you for your help!
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