[Franko]

Hello.
I have 1-D mesh with 10 cells (each cell - 1 meter length).
And I have fixedValue pressure boundary conditions on my boundaries (walls):

inlet(left) p: fixedValue 2
outlet(right) p: fixedValue 1

Internal pressure = 1

So how fvc::snGrad(p) will be calculated on the left and right boundaries? There is no information about this in OpenFOAM guides. Help!

[hjasak]

[(value at the boundary) - (value in the cell)]/distance

Since you are fixing the boundary value, the cell value (solution) will influence your snGrad.

Hrv

[Franko]

Thanks, hjasak!
But could you tell me where I can find this information in OpenFOAM libs?

[hjasak]

fvPatchField.C


// Return gradient at boundary
template<class Type>
Foam::tmp<Foam::Field<Type> > Foam::fvPatchField<Type>::snGrad() const
{
return (*this - patchInternalField())*patch_.deltaCoeffs();
}

[Franko]

Yeah, thanks a lot!