a calculation at the boundary

kebsiali · June 26, 2015, 06:06

hello foamers

I want a variable to have a value of 0 everywhere except at one of the boundaries.
where it will have a value that depends on other fields like u,T,p which are readily calculated.
I need it at runtime because the second step is to use it in a source term.
i started by constructing it in createFields.H but now i need an expression to calculate it
i dont have enough experience with openfoam object oriented conditioning and i dont know what kind of condition to impose.

any idea how the expression should look? something like in the boundary correction ?

thanks for any suggestion

kebsiali · June 26, 2015, 07:39

I think such an expression looks like:

forAll(U.boundaryField(), ???)
{
volScalarField& aaa = U.boundaryField();
aaa = fvc::div(U);
}

Im not sure, just trying random stuff
but i get the following message:

invalid initialization of reference of type ‘Foam::volScalarField& {aka Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh>&}’ from expression of type ‘Foam::GeometricField<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh>::GeometricBoundaryField’
volScalarField& aaa = U.boundaryField();

June 26, 2015, 06:06	a calculation at the boundary "condition to access points at boundaryfield"	#1
kebsiali Member ali alkebsi Join Date: Jan 2012 Location: Strasbourg, France Posts: 82 Rep Power: 14	hello foamers I want a variable to have a value of 0 everywhere except at one of the boundaries. where it will have a value that depends on other fields like u,T,p which are readily calculated. I need it at runtime because the second step is to use it in a source term. i started by constructing it in createFields.H but now i need an expression to calculate it i dont have enough experience with openfoam object oriented conditioning and i dont know what kind of condition to impose. any idea how the expression should look? something like in the boundary correction ? thanks for any suggestion Last edited by kebsiali; June 26, 2015 at 07:40.

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June 26, 2015, 07:39		#2
kebsiali Member ali alkebsi Join Date: Jan 2012 Location: Strasbourg, France Posts: 82 Rep Power: 14	I think such an expression looks like: forAll(U.boundaryField(), ???) { volScalarField& aaa = U.boundaryField(); aaa = fvc::div(U); } Im not sure, just trying random stuff but i get the following message: invalid initialization of reference of type ‘Foam::volScalarField& {aka Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh>&}’ from expression of type ‘Foam::GeometricField<Foam::Vector<double>, Foam::fvPatchField, Foam::volMesh>::GeometricBoundaryField’ volScalarField& aaa = U.boundaryField();