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Use of face centered differences in gradient computation

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Old   August 25, 2011, 05:56
Default Use of face centered differences in gradient computation
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Henning Heiberg-Andersen
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Hi,

According to the recent work of Richrds and Norris (J. Wind Eng Ind.Aerodyn 99 (2011) 257-266), the near ground spike in turbulent kinetic enery in the k-epsilon
model originates from an inconsistency in the discretization. This error can be removed by computing all gradients in terms of face centered differences.

Can this shift be achieved by any of the options in the fvSchemes file?

Best regards,
Henning Heiberg-Andersen
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Old   August 25, 2011, 09:34
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Steven van Haren
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Are you sure this is not already being done?

I think discritization (53) from the paper you refer to is not possible in an unstructered code.

Furthermore, in kEpsilon.C:

Code:
volScalarField G("RASModel::G", nut_*2*magSqr(symm(fvc::grad(U_))));
where fvc::grad(U_) are the gradients at the face.

Is this what you were referring to?
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Old   August 25, 2011, 11:41
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Praveen. C
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I have asked this question before

Gradient at face center of a scalar volume field

and I think there is no such scheme available. Please correct me if I am wrong.
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