Tangential Inlets

Curious

Does anyone out there have experience modelling hydrocyclones or other devices with tangential inlets?

I know that the turbulent anisotropy inherent with the high streamline curvature in these devices necessitates the use of second order closure models (i.e. RSM SSG), but even when I use such a model, the pressure drop predicted by the code (CFX10) seems to severly underpredict the experimentally obtained pressure drop (by a factor of 2). I am running the high resolution scheme as a steady state simulation on a tetra mesh. I am only running single phase and neglecting the air core, does anyone know what type of effect this will have on the pressure drop? I have tried running two phase (water and air core) but get very poor convergence.

Anyway, it would be great to hear of other peoples experience.

Thanks