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July 14, 2012, 20:25 
A question about UEqn sonicFoam

#1 
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Hi, I have a question about the UEqn implemented into sonicFoam, the code of the UEqn is:
Code:
fvVectorMatrix UEqn ( fvm::ddt(rho, U) + fvm::div(phi, U) + turbulence>divDevRhoReff(U) ); Code:
tmp<fvVectorMatrix> kEpsilon::divDevRhoReff(volVectorField& U) const { return (  fvm::laplacian(muEff(), U)  fvc::div(muEff()*dev2(fvc::grad(U)().T())) ); } but after examining the definition of dev2 in src/OpenFOAM/primitives/Tensor/TensorI.H I found the following: is the rateofstrain tensor given by but according to the definition of DivDevRhoReff And manipulating the expression (1) I conclude that the term Code:
+ turbulence>divDevRhoReff(U) If someone can help me with my confusion about this term, I was very thankful
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Felipe G Last edited by lfgmarc; July 15, 2012 at 14:34. 

January 24, 2013, 13:26 

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Quote:
I hope I can find out what is wrong. 

February 15, 2013, 10:07 

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Jens Klostermann
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June 14, 2013, 15:36 

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Sasan Ghomi
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June 17, 2013, 09:57 

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Jens Klostermann
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No, I didn't habe time to work further on this problem.


December 24, 2014, 16:48 

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Dongyue Li
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Quote:


February 1, 2015, 17:49 

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Panagiotis Giannatselis
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Reading Calculating divDevReff I concluded that this term is zero if the fluid is incompressible and near convergence it doesn't concern us. The term remains for stability reasons when we are still far from the solution. If somebody more experienced confirms my thinking, the problem is solved.
I don't feel able to tell you that my point is 100% correct. 

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