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small confusion on the div() term.

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Old   March 7, 2013, 07:29
Default small confusion on the div() term.
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Nikesh Bhattarai
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Hii Foamers,
I am modifying one of the turbulence models. In that process I have to introduce a new term in the source code, D/Dt(k_/omega_) which can be written as d/dt(k_/omega_)+ fvc::div(phi_,k_/omega_) for incompressible flows. Also considering steady state, we have:

D/Dt(k_/omega_) = fvc::div(phi_,k_/omega_)

Now my doubt is::in openfoam, the RHS of equation is solved based on FVM so, when these terms are discretized, is the cell-volume already included in it or do we need to specify it in the source code itself?
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Old   March 7, 2013, 08:19
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Nikesh Bhattarai
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Or to put it in another words......
what I want is "D/Dt(k/omega)" and not "integral of D/Dt(k/omega) dV".
i.e. when I assign this new Field,
volScalarField DDtkw = fvc::div(phi_,k_/omega_)
what I get is DDtkw = integral of div(phi, k/omega) dV
Did I get it right here?
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Old   March 8, 2013, 00:11
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Nikesh Bhattarai
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Nobody with insights in this, really??
I had even posted this problem in another location, yet no response in there too....

http://www.cfd-online.com/Forums/ope...nce-terms.html

Maybe the question is rather clearer in the above mentioned forum.
Anyone???? help!!
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