drag

laura

I must simulate a pipe, in which comes from the outer part water with high velocity, while air comes from the inner part.This water should drag air and take this air till one focus exit. The water can reach 900m/s. This drag should produce one depression, that makes come inside other air. I tried with multiphase approach, and also with lagrangian (the vlum fraction of air is 90%). But doesn´t work. I am not sure also about the geometrie, especcially on the part of the focusing nozzle. Anybody knows, or already did, how can I simulate such a phenomenon (drag+depression creating)? ANy help would be appreciated, about all.