I have tried to simulate in interaction between impeller and volute using several methods, with varied success.

In 2D, I modelled the cross section of a small centrifugal pump. I set up the suction nozzle, impeller region and volute region up as three different faces and meshed them.

After exporting to Fluent, I set up the impeller region as a rotating referrence frame at 500rpm. This provides sensible results for some models, but not all. Sometimes the solution will not converge. In these cases I used water as the fluid, had a velocity inlet at the suction nozzle and a pressure outlet at the discharge of the volute set to 0 Pa.

With three dimensions I tried applying a similar method, with little success. The fluid being moved by the impeller is unable to progress to the volute.

Any help would be greatly appreciated.

[yvonne]

Have you tried giving mass flow inlet and pressure outlet?? Also check if u are giving flowrate in proportion to rpm