Investigation of internal flow pattern of a multiphase axial pump

Abstract

Due to recent advances in computational techniques, single phase performances of pumps can be easily estimated using CFD. However, when the working fluid is a mixture of liquid and gas (multi-phase flow) computations may struggle to capture the more complex physical phenomena that occurs, and the precision of the prediction worsen as the gas volume fraction at pump inlet is increased. To provide reliable benchmark for the improvement of simulations, in this study we experimentally investigated the internal flow pattern of a multiphase pump using high speed camera and high frequency pressure measurements, so as to obtain the data of pressure distribution inside of impeller, or to obtain blade loading, for several gas concentration conditions. Unsteady phenomena were identified at low flow rate conditions, and an explanation of their nature has been attempted.