[Dozer_94]

Hi all,

In my simulation, I have to reset the fixed gradient of a scalar field "s" as a BC on a patch each time step.

Now, I am aware that if all faces of a patch get the same value, you can use

    label BCID = mesh.boundaryMesh().findPatchID("part0");
    if(s.boundaryField()[BCID].type() == fixedGradientFvPatchScalarField::typeName)
    {
        fixedGradientFvPatchScalarField& spatch = refCast<fixedGradientFvPatchScalarField>(s.boundaryFieldRef()[BCID]);
        spatch.gradient() = dp;
    }

See this thread: Updating Boundary Conditions Each Iteration

This will set the normal gradient of scalar "s" on all faces of patch "part0" to value "dp". Which works perfectly. But what if I want to give each face a different value? Say something like this:

    label BCID = mesh.boundaryMesh().findPatchID("part0");  
    if(s.boundaryField()[BCID].type() == fixedGradientFvPatchScalarField::typeName)
    {
        fixedGradientFvPatchScalarField& spatch = refCast<fixedGradientFvPatchScalarField>(s.boundaryFieldRef()[BCID]);
        forAll (spatch, faceI)
        {
            spatch[faceI].gradient() = dp[faceI];
        }
    }

In which "dp" is now not a float, but a list of floats. This does not work, as OF throws the following error:

   sBC.H:32:18: error: request for member ‘gradient’ in 
‘(& spatch)->Foam::fixedGradientFvPatchField<double>::
 <anonymous>.Foam::fvPatchField<double>::<anonymous>.Foam::Field<double>::
  <anonymous>.Foam::List<double>::<anonymous>.Foam::UList<double>::operator[](faceI)’, 
which is of non-class type ‘double’
      spatch[faceI].gradient() = dp[faceI];

Anyone ideas on what is going wrong here?

Thanks in advance,

[einstein_zee]

Originally Posted by Dozer_94

Hi all,

In my simulation, I have to reset the fixed gradient of a scalar field "s" as a BC on a patch each time step.

Now, I am aware that if all faces of a patch get the same value, you can use

    label BCID = mesh.boundaryMesh().findPatchID("part0");
    if(s.boundaryField()[BCID].type() == fixedGradientFvPatchScalarField::typeName)
    {
        fixedGradientFvPatchScalarField& spatch = refCast<fixedGradientFvPatchScalarField>(s.boundaryFieldRef()[BCID]);
        spatch.gradient() = dp;
    }

See this thread: Updating Boundary Conditions Each Iteration

This will set the normal gradient of scalar "s" on all faces of patch "part0" to value "dp". Which works perfectly. But what if I want to give each face a different value? Say something like this:

    label BCID = mesh.boundaryMesh().findPatchID("part0");  
    if(s.boundaryField()[BCID].type() == fixedGradientFvPatchScalarField::typeName)
    {
        fixedGradientFvPatchScalarField& spatch = refCast<fixedGradientFvPatchScalarField>(s.boundaryFieldRef()[BCID]);
        forAll (spatch, faceI)
        {
            spatch[faceI].gradient() = dp[faceI];
        }
    }

In which "dp" is now not a float, but a list of floats. This does not work, as OF throws the following error:

   sBC.H:32:18: error: request for member ‘gradient’ in 
‘(& spatch)->Foam::fixedGradientFvPatchField<double>::
 <anonymous>.Foam::fvPatchField<double>::<anonymous>.Foam::Field<double>::
  <anonymous>.Foam::List<double>::<anonymous>.Foam::UList<double>::operator[](faceI)’, 
which is of non-class type ‘double’
      spatch[faceI].gradient() = dp[faceI];

Anyone ideas on what is going wrong here?

Thanks in advance,

Hey there,

have you tried it this way: spatch.gradient()[faceI] = dp[faceI]

[Dozer_94]

Oh my... Not my brightest moment. Thanks a lot for the superfast reply!