Can free surface model work with other models such as turbulance, baffle pressure drop etc for heavy fluid flow.

The free-surface model will work with a turbulence model (will also work with no turbulence model as well). In this model, you consider having one fluid with variable physical properties varying linearly with the void-fraction (VoF). Baffle pressure drop can only be modeled by having additional user defined source terms for the momentum equations.

Thanks. Can the baffle pressure drop be modeled through the subroutine 'sormom.f'.

Well, I think so... If you think of one or two very thin cell layers and distributed resistance on these cells. BTW, what do you mean exactly by baffle pressure drop?

Thanks for yor reply. There are two types pressure drop regions in the computational domain under my consideration. One is the pressure drop offered by a porous plate and the other pressure drop offered by tube bundle. The first pressure drop region influences the velocity profile of heay fluid and hence the free surface profile. The other influces level of heavy fluid in the domain. Can you throw some light on how these regions can be modeled in a free surface model problem. In the normal fluid flow modeling, I have modeled these regions by baffle pressure drop option and sormom.f option respectively. Whether the same work with free surface modeling. My experience is that it is not working.