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Old   December 19, 2016, 07:37
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longyun wang
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hi,
I am new in openfoam. When reading codes, I can't understand the phi in fvm::div(phi, U). It stands for △·(UU), why don't we write as fvm::div(U, U) and what does phi means exactly.
thanks a lot
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Old   December 19, 2016, 09:23
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Agustín Villa
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Hi,
phi is actually the flux through the cells (so it is not a volVectorField, but a surfaceScalarField). For incompressible solver phi=U, but in case of compressible flows, phi=rho*U. This is why phi is used, you only change its definition in createFields.
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Old   December 21, 2016, 03:34
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thx very much~~
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Old   December 21, 2016, 08:50
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Tobias Holzmann
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By the way, your equation is wrong. Be careful with laplacian and nabla!

@agustinvo, you missed the face area!
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