Experimental Measurements in a Centrifugal Pump Impeller

Abstract

Measurements of the 3-d velocities, total and static pressures have been made in a 0.89 m diameter commercial pump impeller, using air as the working fluid. Results at the peak efficiency operating point show separation of the flow near the shroud on the pressure side of the blade at the leading edge. This separation results in a low energy region which initially travels axially through the impeller to form a wake in the suction side shroud corner region. A region of reversed radial velocity is observed at the outlet, which is due to high blade sweep angle together with the poor guidance given to the flow by the blades in the mid-passage region.