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Initial values of K-Epsilon.

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Old   May 16, 2009, 13:39
Default Initial values of K-Epsilon.
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Manish
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I am doing with a 3-d turbulent unsteady air-hydrogen mixing flow in a closed vessel with energy equation off using a volume weighted density performance. I am using K-epsilon model with turbulent length scale as 7% of hydraulic dia. instead i want to use k & Epsilon values. how can I calculate it.
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Old   June 1, 2009, 22:33
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Anybody.........
help me out.........
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Old   June 3, 2009, 07:23
Default how to calculate k & epsilon values
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amira maizi
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Quote:
Originally Posted by sijaria2u View Post
Anybody.........
help me out.........
k=10^{-3}*v^{2}_{0}

\epsilon= \frac{k^{3/2}}{0.5*d}

d is the hydraulic diameter of the face boundary


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Old   June 3, 2009, 09:48
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thanks, the problem I was facing was due to low inlet velocity model overpridicted turbulence and hence diffusio, now I have tried with K/100 and epsilon/100 values. results hv improved.
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