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Marat Hoshim March 19, 2001 09:24

Transformation of k and eps equations
 
Hi all,

in some papers using the SST k-omega model there's said, that the k and eps equations were transformed into the k and omega formulation. Does someone know a detailed reference, that shows how this transformation is done step by step.

Regards, Marat

Doug March 20, 2001 08:07

Re: Transformation of k and eps equations
 
You might try Menter's paper(s) where he first introduces the SST model. They aren't overly detailed, but they do give the basic way his model combine the k-epsilon and k-omega.

The references are:

Menter, F. R., "Improved Two-Equation k-omega Turbulence Models for Aerodynamic Flows", NASA TM-103975 .

Menter, F. R., "Two Equation Eddy Viscosity Turbulence Models for Engineering Applications", AIAA Journal, Vol. 32, No. 8, August 1994.

sylvain March 20, 2001 08:46

Re: Transformation of k and eps equations
 
I don't have any reference, but you should look to papers from Aupoix et al. if there is any.

The main idea is the following :

let phi be any function of k and eps such as :

phi = k^{alpha} * eps^{beta}

it comes :

(1/phi)d(phi)/dt = alpha * (1/k) d(k)/dt + beta * (1/eps)d(eps)/dt

since d(k)/dt and d(eps)/dt are already known, it is possible to write the equation of any kind of phi. The difficulty is then to deal with the cross terms (coming form the viscous term).

hope that helps,

Sylvain


sylvain March 21, 2001 10:15

Re: Transformation of k and eps equations
 
I forgot :

omega = eps/k


Eren10 March 7, 2011 09:33

Does someone know how to transform the k-epsilon for the SST model.

I need to know how Menter came to the closure coefficients:

\sigma_{w2} = 0.856 and \beta_2 = 0.0828


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