Detection of the invisible blade pressure-side cavitation in pump impeller based on acoustic measurement and numerical prediction

Abstract

Based on the combination of experiment and numerical simulation, this paper analyzed the cavitation mechanism and cavitation phenomenon of a coolant pump under large-flow working conditions in detail. In view of the fact that cavitation occurs on the pressure surface of blade that is invisible under this working condition, the calibration of inception cavitation is performed by acoustic method, critical cavitation is judged by the head drop by 1%, and all of them are visualized through CFD numerical simulation. Based on qualitative and quantitative analysis, from inception status to critical status of cavitation and then to large-scale cavitation, cavitating flow in the blade channel is carefully analyzed. In addition, the relevance between cavitation vapor volume and pressure in impeller is established. All of these researches provide an analysis strategy for calibrating the hidden cavitation bubbles in blade channel.