[openfoammaofnepo]

Dear All,

For the time discretization terms (explicit or implicit), like(from https://github.com/OpenFOAM/OpenFOAM...eFoam/pEqn.H):

    fvScalarMatrix p_rghEqn
    (
        fvm::ddt(psi, p_rgh)
      + fvc::ddt(psi, rho)*gh
      + fvc::ddt(psi)*pRef
      + fvc::div(phiHbyA)
      - fvm::laplacian(rhorAUf, p_rgh)
     ==
        parcels.Srho()
      + surfaceFilm.Srho()
      + fvOptions(psi, p_rgh, rho.name())
    );

In the above piece of codes, the explicit term "fvc::ddt(psi)*pRef" only changes between time steps (the outer SIMPLE loops), while in iterations (PISO) for each time step, they are constant. Is this understanding correct?

Is this statement also valid for the explicit temporal discretization terms, such as fvm::ddt(psi, p_rgh)?

Thank you so much!