[bryant_k]

Hello everyone
I want to change values of a surfaceSalarField sphi at boundary 'surface'.To other regions,the values keep default.So I write a piece of code :

sphi=sigma*(interpolate(U) &mesh.Sf())-fvc::snGrad(ha);

label patchI=mesh.boundaryMesh().findPatchID("surface");
forAll(sphi,patchI)
{
sphi[patchI]=sigma*(interpolate(U) &mesh.Sf());
}

But this is wrong.So can you tell me how to modify the above code?

regards!

bryant