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-   -   eddy viscosity (http://www.cfd-online.com/Forums/cfx/22388-eddy-viscosity.html)

Mike April 3, 2006 16:03

eddy viscosity
 
Hi all,

I have one more question. The cfx manual states that eddy viscosity should be of the order of 1000 times the dynamic viscosity for a fully turbulent flow. I am checking the values of eddy viscosity in the domain and it varies 0-300 times to dynamic viscosity. How does this affect the results? So if most part of the domain is not fully turbulent what happens? any help would be very much appreciated.

Mike

Robin April 4, 2006 13:12

Re: eddy viscosity
 
Hi Mike,

It's hard to say exactly what the effect will be. Most Turbulence models are created by making some simplifying assumptions about the Reynolds averaged flow. These assumptions may no longer apply.

See how your results compare when you run laminar flow. You could also try the SST transition model, although I suggest reviewing the documentation carefully to ensure its applicability as well.

Regards, Robin


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