Influence of Blade Leading-Edge Shape on Rotating-Stalled Flow Characteristics in a Centrifugal Pump Impeller

Applied Sciences

Zhengwei Wang¹  Ran Tao¹  Hongying Luo²  Jiandong Yang² 

[1] Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China;State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China;

关键词: centrifugal pump;    leading-edge shape;    rotating stall;    flow simulation;    pressure pulsation;   

DOI  :  10.3390/app10165635

来源: DOAJ

【 摘 要 】

Rotating stall, which is a common phenomenon in turbomachinery, strongly relates to the flow rate condition. In centrifugal impellers, rotating stall was induced by the incidence angle on blade leading-edge at partial-load. The blade leading-edge shape also influences the rotating stall because of the subtle change of local flow-field. In this study, the influence of blade leading-edge shape on rotating-stalled flow characteristics was studied in a six-blade centrifugal pump impeller. The stall pattern was “alternating”: Three passages were stalled, three passages were well-behaved, and the stalled and well-behaved passages occurred alternately. The stalled flow characteristics can be studied without the interruption of stall cell movement. Four types of blade leading-edge (blunt, sharp, ellipse, and round) were numerically compared based on the initial typical impeller and the numerical–experimental verification. The numerical comparison shows that the leading-edge shape has a strong influence on the stalled flow pattern, velocity, pressure, turbulence kinetic energy, and flow-induced noise inside impellers. The blunt and sharp leading-edge impellers had a similar internal pattern; the ellipse and round leading-edge impellers were also similar in the internal flow-field. Pressure pulsation analysis showed more obvious differences among these impellers. The main frequency and the pulsation peak–peak values were completely different because of the slight leading-edge shape differences. It revealed the impact of leading-edge geometry on the transient flow-field change under the same incidence angle conditions. It also provided reference for influencing or controlling the rotating stall by blade profile design.

【 授权许可】

Unknown