CFD analysis of the air-water bubbly flow in a multiphase rotordynamic pump impeller

The numerical simulation of gas-liquid two-phase flow in an impeller of multiphase pumps is formidable and few transient analyses and two-phase flow analyses have been carried out. In this paper, based on the Navier-Stokes equations and the Two-Fluid Model, the air-water bubbly flow in a multiphase rotordynamic pump impeller has been studied through CFD analysis with SIMPLEC algorithm. The drag force and added mass force are considered in this model. By comparing the pump heads through calculation and experiment in the 15% void fraction condition, the reliability of the numerical method is verified. The numerical results demonstrate that the gas blocking phenomenon can be avoided effectively if relatively small radical dimension is adopted in the flow passage, and vortex mainly occurs in the impeller inlet where the gas will be inclined to gather, so the hydraulic design of the inlet region should be improved.