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Turbulence Model in axisymmetric nozzle simulation |
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#1 |
New Member
Join Date: Dec 2012
Posts: 11
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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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#2 |
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OJ
Join Date: Apr 2012
Location: United Kindom
Posts: 473
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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.
OJ |
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#3 |
New Member
Join Date: Dec 2012
Posts: 11
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Yes, Just tried realizable.. it also shows a shock wave
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#4 |
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Jeff Yam
Join Date: Sep 2017
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Hi, could i ask you what do you mean by diffusive?
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#5 |
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Arjun Kalkur
Join Date: Sep 2017
Posts: 12
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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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#6 |
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Jeff Yam
Join Date: Sep 2017
Posts: 11
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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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