Vanishing volume fraction

Astrid

Hi all,

I am working on a CFD simulation with two phases (two gases), one inlet, and two outlets. The volume fraction of the first is around 0.99, the second is around 0.01. You can argue about if one should perform multiphase calculations with such a low fraction but that is not what I want to discuss here.

The problem is that at the inlet the fluids enters the domain with the ratio as specified above but that the smallest fraction never ever reaches the outlets. Due to some strange kind of reason, the volume fraction vanishes (<1e-10). I have changed the scheme, performed double precision, switched the multiphase model between two continuous phases and a continous/dispersed couple (I do not want to use the homogeneous option because I need two velocity fields). No satisfying result at all.

What is hapening here? Any suggestion?

Thanks for reading, Astrid.