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-   -   how to solve turbulent viscosity limited ? (https://www.cfd-online.com/Forums/fluent/39994-how-solve-turbulent-viscosity-limited.html)

daniel sin March 7, 2006 00:02

how to solve turbulent viscosity limited ?
 
anyone know it? turbulent viscosity limited to viscosity ration of 1.000e5 in 123 cells

Rizwan March 7, 2006 02:02

Re: how to solve turbulent viscosity limited ?
 
check your initialized values. the turbulent viscosity and dissipation values should be very low. refer to fluet help files tutorial guide on boundary conditions and calculation for turbulence quatities.

hope this helps.

CFD March 7, 2006 02:13

Re: how to solve turbulent viscosity limited ?
 
Increase limit of turbulent viscosity from 100000 to 1000000 in the panel solve-->control-->limits.

Hope this help.

Rajesh March 7, 2006 02:15

Re: how to solve turbulent viscosity limited ?
 
Another useful information:

http://www.cfd-online.com/Forum/flue...cgi?read=29389

Rajesh

Freeman March 7, 2006 14:22

Re: how to solve turbulent viscosity limited ?
 
I think increasing the limit is not a good idea since you will be only "postposing" the warning message: I mean, if you increase the limit, solver would increase each iteration the turbulent viscosity. Perhaps you might not be noticed again about the warning, but in the final calculation your turbulent viscosity would be, i.g. 500,000 and if your fluid is water, this turbulent viscosity would be indicating that your fluid at the turbulence state is almost cement!

The explanation given by zxaar time ago that Rajesh has recovered in a link again was (and it is) simply great.


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