[Twist]

Hi all!

I have a problem with the gradient of the surface field muEff. The original piece of code from InterFoam is

    surfaceScalarField muEff
    (
        "muEff",
        twoPhaseProperties.muf()
      + fvc::interpolate(rho*turbulence->nut())
    );

    fvVectorMatrix UEqn
    (
        fvm::ddt(rho, U)
      + fvm::div(rhoPhi, U)
      - fvm::laplacian(muEff, U)
      - (fvc::grad(U) & fvc::grad(muEff))
    //- fvc::div(muEff*(fvc::interpolate(dev(fvc::grad(U))) & mesh.Sf()))
      - rho*g
    );

Now I would expect that the following part of the fvSchemes would make an error:

gradSchemes
{
    default		none;
    grad(p)		Gauss linear corrected;
    grad(p_rgh)		Gauss linear corrected;
    grad(pcorr)		Gauss linear corrected;
    grad(U)		Gauss linear corrected;
    grad(alpha1)	Gauss linear corrected;
}

because the default is none and a grad(muEff) part is missing but it doesn't. The solver runs without an error. If I change muEff to a volScalarField I get the expected error and have to state a scheme for grad(muEff).

Is this a bug or did I just miss something?

Thanks!