Influence of blade trailing edge profile on pressure pulsation in high-speed centrifugal pump

Abstract

High-speed centrifugal pump can easily lead to severe pressure pulsation due to complex flow, seriously influencing the stable operation. The slant-cutting suction surface to the blade trailing edge midpoint is proposed to improve the fluid flow and dynamic–static interference at the blade outlet for the high-speed pump. Based on large eddy simulation method, the pressure pulsations in a high-speed centrifugal pump were comparatively analyzed under different blade edge profiles with slant-cutting angles of 15°, 30°, and 45°. The numerical performance curves for an OB high-speed centrifugal pump are basically consistent with the experimental ones. In addition, the heads and efficiencies for MB15, MB30, and MB45 pumps are all higher than those of the OB high-speed centrifugal pump under all working conditions, and the head increases to the maximum of 1.24% when the slant-cutting angle is 15°. The high-intensity pressure pulsation at the blade outlet is closely related to the shedding periodic vortex from the blade pressure surface and flow separation under high-speed conditions. Compared with the OB high-speed centrifugal pump, the pressure intensity is decreased by 3.92% and 4.07% at tongue area for MB15 and MB30 pumps, respectively.