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sebastian February 6, 2012 06:04

High speed flow with Launder-Sharma-k-epsilon-Model
Dear All,

I need to run a compressible high speed nozzle flow in OF on a low-Re mesh (y+<1).
So far I did my calculations with the kOmegaSST turbulence model and it worked quite nice.
Now I have to use the k-Epsilon turbulence model on the same mesh.
The only low-Re k-epsilon turbulence for a compressible case available in OF is the one by Launder and Sharma.
I compared the code of the LaunderSharmaKE with the standard kEpsilon model and found some differences as additional source-terms as well as some turbulent Reynolds-number functions.

So I have some questions, hoping anybody can answer these:
  1. Is it okay to use the Launder-Sharma k-e-model for such a case?
  2. How does this turbulence model behave in regions far away from the wall? Does it differ from the standard k-epsilon model or are thes modifications only due to near wall regions?
  3. As my y+-values are everywhere below 1.0, I can not use wall functions. Any other suggestions to solve this flow problem with a k-epsilon model?

Thanks in advance!

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