Effect of wear-ring clearance on cavitation flow and performance of centrifugal pump with inducer
XIAO Liqian1, LI Yibin1,2, LIU Yi1,2, BI Zhen1, ZHAO Weiguo1,2
1.School of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050, China; 2.Key Laboratory of Fluid Machinery and Systems, Lanzhou, Gansu 730050, China
Abstract:In order to investigate the effect of wear-ring clearance on the cavitation performance of the centrifugal pump with THE pre-positioned inducer, the cavitation flow and performance in the centrifugal pump with the pre-positioned inducer were numerically simulated with four different projects which were 0.15,0.25,0.40 mm and 0.60 mm based on the RNG k-ε turbulent model combined with Rayleigh-Plesset Homogeneous cavitation model,and compared with experimental results. The results show that the size of the wear-ring clearance has a greater influence on the external performance and cavitation performance; with the increase of the wear-ring clearance, compared with 0.15 mm, the total head efficiency and the head efficiency of the impeller decrease, the changes of the head are up to 0.60%,4.21%,and the changes of the efficiency are up to 6.50%,9.32%. Moreover, the head and efficiency of the inducer increase, and they are up to 29.86%,28.40%.The cavitation curves wave with the increase of the wear-ring clearance and the decrease of the cavitation number, and the wider the clearanceis, the more obvious the flactuationis. The cloudy cavitation bubbles are distributed on the pressure surface that is close to the front shroud, which causes cavitation instability, and the wider the clearanceis, the more the cavitaionis,the greater the critical cavitation numberis. It is found that the factors that influence the cavitation instability of the pump are possibly related to the impact of leakage high-pressure fluid of the wear-ring outlet on the main flow,the occurrence of cavitation at the intersection of impeller inlet and wear-ring clearance outlet and the change of the outlet flow angel caused by cavitating in the pre-positioned inducer.
肖丽倩, 黎义斌,, 刘宜,, 毕祯, 赵伟国,. 口环间隙对诱导轮离心泵空化流动和性能的影响[J]. 排灌机械工程学报, 2016, 34(8): 657-664.
XIAO Liqian, LI Yibin,, LIU Yi,, BI Zhen, ZHAO Weiguo,. Effect of wear-ring clearance on cavitation flow and performance of centrifugal pump with inducer. Journal of Drainage and Irrigation Machinery Engin, 2016, 34(8): 657-664.
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