Abstract:In order to study the influence of the oblique trimmed impeller on the stability of the performance curves of pumps, the centrifugal pump(IS 65-50-174)was chosen as the research object. The performance curves of the pump with original impeller and the oblique trimmed impeller were obtained by the experiment, while the corresponding internal flow field and the pressure fluctuations were acquired from the unsteady numerical simulation with SST turbulence model. The experimental results show that the centrifugal pump with the oblique trimmed impeller could eliminate the instability of the performance curve and consume more shaft power at the reduced flow rate. By analyzing the internal flow field at 0.2, 0.3 and 0.4 times of the designed flow rate, some conclusions could be got: With the decrease of the flow rate, the low energy zone in the original impeller transferred from the front shroud to the rear shroud.While the recirculation zone of the oblique trimmed impeller occurs near the rear shroud and its intensity of the recirculation increases with the decrease of the flow rate. The analysis of the pressure pulsation at the impeller outlet showed that the pulsation at the low frequency became lower in the oblique trimmed impeller compared with the original impeller, which indicates that the instability of the flow at the impeller outlet becomes lower.
曹睿, 袁寿其*, 司乔瑞, 崔强磊, 盛国臣. 离心泵叶轮斜切对出口回流及驼峰特性的影响[J]. 排灌机械工程学报, 2018, 36(12): 1227-1232.
CAO Rui, YUAN Shouqi*, SI Qiaorui, CUI Qianglei, SHENG Guochen. Influence of oblique trimmed impeller on recirculation at impeller outlet and stability of performance curves. Journal of Drainage and Irrigation Machinery Engin, 2018, 36(12): 1227-1232.
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