# Initial values of K-Epsilon.

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 May 16, 2009, 13:39 Initial values of K-Epsilon. #1 New Member   Manish Join Date: Apr 2009 Posts: 3 Rep Power: 8 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.

 June 1, 2009, 22:33 #2 New Member   Manish Join Date: Apr 2009 Posts: 3 Rep Power: 8 Anybody......... help me out.........

June 3, 2009, 07:23
how to calculate k & epsilon values
#3
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amira maizi
Join Date: Mar 2009
Posts: 8
Rep Power: 8
Quote:
 Originally Posted by sijaria2u 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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 June 3, 2009, 09:48 #4 New Member   Manish Join Date: Apr 2009 Posts: 3 Rep Power: 8 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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