Numerical prediction of rotating stallin a low-specific speed centrifugal pump. (July 2018)

• Record Type: Journal Article
• Authors: Wang, C; Feng, J J; Luo, X Q; Lu, J L; Zhu, G J
• Is Part Of: IOP conference series. Volume 163(2018)
• Publication Date: 2018-07
• Subjects: Earth sciences -- Periodicals; Environmental sciences -- Congresses; Environmental sciences -- Periodicals; 550.5
• DOI: 10.1088/1755-1315/163/1/012091
• Languages: English
• ISSNs: 1755-1307

Abstract

Abstract: Rotating stall is a common unstable flow phenomenon in centrifugal pumps, which usuallyoccurs in part-load conditions. Rotating stall will cause performance instability when thepump is running, and even excite the resonance of the whole pump system in someextreme cases. In this paper, the stall phenomena at part-load conditions have beeninvestigated by CFDsimulation for a centrifugal pump. The CFD results have beencompared with the experiments, including characteristic curves, internal flow structures andcorresponding frequency spectrum analyses. Furthermore, a parameter named theblockage coefficient for the pump impeller passage is put forward to quantitativelyevaluate the magnitude of stall.The large-scale vortex in the stalled channel is defined as astall cell.At the operation condition Q=0.35Q0, five rotating stall cells can be observedin the impeller, which propagate among different impeller channels with a rotatingfrequency lower than that of the impeller. From the frequency spectrum analysis, the mainfrequency of the stall cells is about 23.4% of the impeller rotational frequency, resulting in4.68% for each stall cells. For the operation condition of Q=0.38Q0, a "stationary stall"phenomenon has been observed in the impeller passages.