multiphaseEulerFoam - sensitive to many parameters (unphysical results)
 

I am running multiphaseEulerFoam for a 2D channel with a given inlet water velocity and inlet air from porous walls.
I am obtaining totally different results if I use constant deltaT or variable deltaT (Co < 0.2). Also, I obtained different results by changing nCorrectors from 1 to 2 or 3, or by modifying nOuterCorrectors (a different result for each setting...)
Finally, modifying residualPhaseFraction and residualSlip change a lot the final steady-state solution.
Does anyone know what is happening? Am I doing something wrong?
Does anyone know a validation case for multiphaseEulerFoam? Because all tutorials I saw and even some research papers just show colors ("phases") mixing together...