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Equations of k-Epsilon Model

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Old   March 29, 2015, 13:57
Default Equations of k-Epsilon Model
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Hello,

In the theory guide, it is noted that the term 3*\mu_{t} in Equation 2.25 (p. 85) for the turbulence production is based on the “frozen stress” assumption [54]. This prevents the values of Epsilon and k becoming too large through shocks, a situation that becomes progressively worse as the mesh is refined at shocks.

I don't understand this explanation. What is meant by ''frozen stress'' and what is the significance of ''shocks'' in this context ?

Thank you for your help
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Old   March 29, 2015, 19:02
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I am no expert in turbulence modelling - the manual has a reference for that statement so you will have to look up the reference.

But you should be aware that the shocks they are referring to are compressible flow shock waves.
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