Two Fluids Flow
 

Hi everybody
I'm trying to model a flip-bucket with two fluids (air and water). simulation solves the flow on chute but when the flow reaches to the lip of the flip-bucket, simulation can not solve the pressure (pressure iteration did not converge at ITMAX). I've totally tried lot's of conditions for example VOF method, different mesh size, turbulence model, number of iteration, time step, but didn't work. does anybody have an Idea?
thanks.

Hello Yaser,
I think you can model a Flip-bucket with one fluid free surface flow in F3D. You can use the air entrainment model alongwith the simulation to check on the air entrained in the water.

If for the simulation you believe that there is a large amount of air entrainment to have density change then you can also activate the density model and in case if you are also modelling the downstream area then you can also have the drift flux model activated to allow the trapped/entrained air to escape to the surface.

Hi, did you find what was the problem??
I had this problem too!
I also tried density evaluation and drift flux model but no correct answers!!
I'm working on U-shaped spillway.