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K omega SST equations in Openfoam

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Old   March 13, 2020, 07:09
Question K omega SST equations in Openfoam
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Tom
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Hi All,
I'm looking at the k-mega SST equations for the value of omega in openfoam and i noticed that two different equations are used:


The standard omega= k^0.5/CMu*L
https://www.openfoam.com/documentati...omega-sst.html


And theturbulentMixingLengthFrequencyInlet
https://www.openfoam.com/documentati...frequency.html


where omega is defined as omega =Cmu^0.75* k^1.5/L


My question is why there are two different definitions of omega and which is correct to use for turbo-machinery internal flows?
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Old   March 13, 2020, 23:49
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(k^3/2*cmu^3/4)/L is the expression for epsilon. Using SI units, it results m^2/s^3.


And I think that the other expression is wrong. Omega is equal to epsilon/(cmu*k). So, omega=k^1/2/(cmu^1/4*L). This expression results s^-1 in SI units.
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Old   May 6, 2020, 09:41
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Quote:
Originally Posted by tom.opt View Post
Hi All,
I'm looking at the k-mega SST equations for the value of omega in openfoam and i noticed that two different equations are used:


The standard omega= k^0.5/CMu*L
https://www.openfoam.com/documentati...omega-sst.html


And theturbulentMixingLengthFrequencyInlet
https://www.openfoam.com/documentati...frequency.html


where omega is defined as omega =Cmu^0.75* k^1.5/L


My question is why there are two different definitions of omega and which is correct to use for turbo-machinery internal flows?
So i just rechecked those links and it seems that the formulas have been updated and now the same formulas are shown on both links
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