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How to create additional variable for the eddy viscosity ratio

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Old   October 24, 2013, 21:16
Question How to create additional variable for the eddy viscosity ratio
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Tom
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Hi there

Can anyone please tell me how to create an additional variable for the eddy viscosity ratio in CFX-pre so that I can use it in CFX-post for boundary layer flow separation analysis.

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Tom
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Old   October 24, 2013, 21:46
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Glenn Horrocks
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In CFD-Post, create a new variable (the "x" button) and give it the expression Eddy Viscosity/Dynamic Viscosity.

Pretty simple.
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Old   October 24, 2013, 23:38
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Got it

Thanks Glenn
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Old   October 30, 2013, 04:36
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may I ask what does it really express and how can I use it for cases?

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Old   October 30, 2013, 06:00
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It tells you how much of the viscosity in the model comes from the turbulence model and how much comes from the laminar viscosity. As the model becomes highly turbulent this ratio gets large. For some applications a ratio of 1 is defined as the transition to turbulence (but in my opinion it is not a very good definition )
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