Investigation of Unsteady Pressure Pulsation and Internal Flow in a Centrifugal Pump under Low Flow Rate

In order to study the unsteady pressure pulsation and internal flow in a centrifugal pump under low flow rate, numerical calculation of a centrifugal pump was carried out. The accuracy of the numerical calculation method was verified with the external characteristic test. The characteristics of the unsteady pressure pulsation and internal flow of the centrifugal pump were analyzed in detail. The results show that the interaction between the impeller and the volute has a significant effect on the unsteady pressure pulsation of the centrifugal pump. The essential reason of the periodic pressure pulsation was explained, and the evolution of separation vortex formation and collapse in the impeller was presented. Regulation of the generation and development of the high pressure zone in the volute was revealed. With the reduction of the flow rate, the influence of the low pressure zone in the impeller is enhanced and the pressure near the volute tongue is decreased. The results can provide a reference for the centrifugal pump design and optimization.