Analysis of Backflow Vortex and Cavitation of High Speed Centrifugal Pump

doi:10.3901/JME.2020.04.095

Abstract

Abstract: The high specific speed of the high-speed centrifugal pump is very high. Therefore, the inlet and the inside of the high-speed centrifugal pump are usually high-incidence areas such as recirculation vortex and cavitation cavitation. As far as the current research status is concerned, whether the cavitation suppression device such as the orifice plate can suppress the reflux vortex is relatively rare. The pre-cavitation suppression device for the induction wheel is optimized. A total of 25 schemes for changing the geometric parameters such as the front and rear inclination angles of the device are designed for numerical simulation analysis. Based on this, it is preferable to select the five schemes with the best hydraulic performance and to carry out the fraction of the reflux vortex and the intensity. It focuses on whether the change in the alpha angle affects the associated reflow rate and pressure. At the same time, the influence of the high-speed centrifugal pump induction wheel and the internal cavitation occurrence and development of the impeller is analyzed. Finally, two optimal schemes of -10°/20° and -20°/10° are determined, which are superior to other schemes in terms of the strength and influence range of the reflux vortex; the gas phase volume fraction is inside the induction wheel and the impeller. The distribution area is small and the strength is low. Under the design condition, the efficiency of the pump is increased by about 2% compared with the 0°/0° scheme, which better suppresses the reflux vortex and improves the anti-cavitation performance of the high-speed pump. It provides a certain reference for the optimization design of internal cavitation of high-speed centrifugal pump.

Key words: high-speed centrifugal pump, hackflow vortex, havitation suppression device, dip angle

CLC Number:

TH311

SONG Wenwu, SHI Jianwei, WEI Lichao, HU Shuai, LUO Xu, CHEN Jianxu. Analysis of Backflow Vortex and Cavitation of High Speed Centrifugal Pump[J]. Journal of Mechanical Engineering, 2020, 56(4): 95-103.

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