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Kolmogorov scale .... LES

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Old   August 8, 2005, 08:45
Default Kolmogorov scale .... LES
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LESer
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Hello,

I am doing some LES of a reacting flow and I need to calculate some values. How can I calculate the Kolmogorov timescale and the Kolmogorov Reynolds Number? Also how can I calculate the dissipation rate (epsilon)?

Thanking you all.
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Old   August 12, 2005, 00:01
Default Re: Kolmogorov scale .... LES
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yuan
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I guess you need read a textbook. Select large scales, estimate the dissipation scales by using the Komogorov relations and then estimate epsilon.
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Old   July 2, 2015, 19:48
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Hello LESer,
Did you find how to calculate kolmogorov length scale in LES? I really appreciate if you could give me some help on this.
Thanks,
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Old   July 3, 2015, 03:38
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Filippo Maria Denaro
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there is no Kolmogorov scale in LES ! the smallest scale is defined by the filter lenght, not by the molecular viscosity and lies in the inertial subrange.
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Old   July 3, 2015, 05:36
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FMDenaro thank you very much for your reply. Can you tell me a way to calculate this smallest length scale? I just need a way to calculate something similar to kolmogorov length scale? Can I write a user defined function for kolmogorov length scale maybe? If you could give me some help on this I really appreciate it.
Thank you very much
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Old   July 3, 2015, 05:54
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Kolmogorov scale is dictated by the physics of the problem.
LES provides the smallest scale at about twice grid step size. That has nothing to do with kolmogorov scale
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Old   July 3, 2015, 06:01
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FMDenaro, thank you very much for your reply. Is there any way I can calculate and see that smallest scale in Fluent? I really appreciate your help. I just need to calculate something corresponding to kolmogorov length scale in LES. Thanks a lot.
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