[l_r_mcglashan]

Dear all,

I've been messing about with the momentum equations in bubbleFoam to try and get an implementation of the product elimination algorithm so that the drag forces are solved for fully implicitly.

If I have an fvVectorMatrix, UEqn;

UEqn =
fvm::ddt(U)
+ fvm::div(phib, U)

should I not be able to reconstruct it as follows:

UEqnReconstructed = fvm::Sp(UEqn.A(),U) - UEqn.H();

If I do this UEqnReconstructed does not appear to equal UEqn, as the simulation results on the bubbleColumn tutorial are different. Is the above correct?