Experimental and numerical investigation on the effect of tip leakage vortex induced cavitating flow on pressure fluctuation in an axial flow pump

In this paper, the cavitating flow and pressure fluctuation in tip region were simulated based on Delayed Detached Eddy Simulation (DDES). The high-speed photography transient measurements employed to capture cavitation structures fluctuation. numerical results show a reasonable agreement with available experiments. maximum errors of head efficiency are 2.9% 2.2%. impeller rotation dominants field, some obvious high-frequency components induced by flow. Increasing rate from 0.8Qopt 1.2Qopt, amplitudes frequency domain P2 decrease 0.13 0.08. There more harmonic-frequency at 0.8Qopt, including 5BPF, 6BPF, 7BPF. Suction-side-perpendicular vortices (SSPCVs) appeared severe conditions, which leads collapse triangular cloud. spatial-temporal evolution SSPCV was divided into three stages: Generating stage, Shedding Dissipating stage. fluctuates significantly passage caused SSPCV. dominant P3 vary 0.031 0.089, as number decreased 0.582 0.231. particular, there is an low-frequency N∗ = 0.5 shown domains P3.