Investigation of cavitation and flow characteristics of tip clearance of bidirectional axial flow pump with different clearances

With the increasing application of bidirectional axial pump, it is necessary to study the flow and cavitation characteristics of bidirectional pump. In this paper, the cavitation and flow characteristics of the tip clearance under different clearances and different cavitation numbers of the S-hydrofoil bidirectional axial flow pump were studied by combining experimental and numerical simulation methods under reverse operation conditions. The section of the bidirectional pump was experimentally studied by high-speed photography and pressure pulsation. Based on the method of RANS, the SST-CC turbulence model and ZGB cavitation model were used to simulate the clearance cavitation of the bidirectional pump, and the cavitation morphology, velocity distribution, clearance vortex structure and energy distribution of blade tip clearance were investigated. The study reveals the flow characteristics of the clearance flow field of the bidirectional pump, and provides reference for the design and operation of it.