multiphase modeling question

liang

I am working on a multiphase problem. It is a milling chamber, having two inlets and one outlet. One inlet is for pressured feeding gas, and one for feeding gas and particle input. The outlet is pressure outlet. The flow inside chamber is turbulent, and I need to treat gas as compressible ideal air. Particle loading volume ratio is around 0.3%, size of particle is 300 um. So which mixture model is more feasible for my problem and how to define boundary conditions? any suggestions is welcome.