Air-water two-phase flow experimental and numerical analysis in a centrifugal pump

The paper presents experimental and numerical investigations performed on a single stage, single-suction, horizontal-orientated centrifugal pump in air-water two-phase non condensable flow conditions. Experimental test loop allows performing controlled values of air void fraction for different water flow rates for a several rotational speeds. Global pump heads and efficiencies are obtained for several inlet air void fraction values at different rotating speeds up to pump performance breakdown. Similarity laws under two-phase flow condition are investigated at three selected rotating speeds. Numerical calculations are also performed using URANS approach including k-e turbulence and inhomogeneous two-phase models for nominal rotational speed, the results of which are used to understand some specific experimental results.