// * * * * * * * * * * * * * * * * NET FORCES * * * * * * * * * * * * * * * //
vectorField netForces(mesh.boundary().size(), vector::zero);
Info << nl;
forAll(netForces, patchI)
{
netForces[patchI] = gSum(mesh.Sf().boundaryField()[patchI] & sigma.boundaryField()[patchI]);
Info << "patch " << mesh.boundary()[patchI].name() << " net force is "
<< netForces[patchI] << " N" << endl;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
