volVectorField U
(
    IOobject
    (
        "U",
        runTime.timeName(),
        mesh,
        IOobject::NO_READ,
        IOobject::AUTO_WRITE
    ),
    mesh,
    dimensionedVector("0", dimVelocity, vector::zero)
);


volScalarField H
(
    IOobject
    (
        "H",
        runTime.timeName(),
        mesh,
        IOobject::NO_READ,
        IOobject::AUTO_WRITE
    ),
    mesh,
    dimensionedScalar("0", dimLength, 0)
);

// Create volume-to surface mapping object
volSurfaceMapping vsm(aMesh);