[estang]

I want to understand the compressible buoyant solvers in OpenFOAM.

First: Why the gravity is reconstructed from surface fluxes here in buoyantSimpleFoam?

            UEqn()
         ==
            fvc::reconstruct
            (
                (
                  - ghf*fvc::snGrad(rho)
                  - fvc::snGrad(p_rgh)
                )*mesh.magSf()
            )
        );

Is there any more difference to compressible solvers without buoyancy than this gravity term in momentum equation and the radiation term in energy equation?

Am i right if i say that it's not possible to add a body force in (already compiled) compressible solvers without buoyancy?

[acs]