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.
[1]罗先武,张瑶,彭俊奇,等. 叶轮进口几何参数对离心泵空化性能的影响[J]. 清华大学学报(自然科学版),2008,48(5):836-839. LUO Xianwu, ZHANG Yao, PENG Junqi, et al. Effect of impeller inlet geometry on centrifugal pump cavitation performance[J]. J Tsinghua University(sci & tech), 2008, 48(5): 836-839.(in Chinese)[2]刘宜,李永乐,韩伟,等. 离心泵的进口几何参数对泵空化性能的影响[J]. 兰州理工大学学报,2011,37(1):50-53. LIU Yi, LI Yongle, HAN Wei, et al. Effect of geometric parameters of centrifugal pump inlet on its cavitation performanc[J] Journal of Lanzhou University of Technology, 2011, 37(1):50-53.(in Chinese)[3]张永学,宋鹏飞,许聪,等. 预旋调节对离心泵空化影响的试验与数值模拟[J]. 农业机械学报,2014,45(9):131-137. ZHANG Yongxue, SONG Pengfei, XU Cong, et al. Experimental and numerical investigations of cavitation in a centrifugal pump with pre-whirl regulation[J].Transactions of the CSAM, 2014,45(9):131-137.(in Chinese)[4]SAMANODY M A E, GHORAB A, MOSTAFA M A F. Investigations on the performance of centrifugal pumps in conjunction with inducers[J]. Ain shams engineering journal, 2013, 5(1):149-156.[5]舒安庆, 张生, 赵彦修. 加装诱导轮改善离心泵抗汽蚀性能[J]. 化工设备与管道, 2003, 40(3):34-36. SHU Anqing, ZHANG Sheng, ZHAO Yanxiu. Use of inducer for improving property of anti-cavitation of centrifugal pump[J]. Process equipment & piping, 2003, 40(3):34-36.(in Chinese)[6]HASSAN W, BARRE S, LEGOUPIL S. Study of the behavior of vapor fraction in a turbopump inducer using an X-ray measurement technique[J]. Experiments in fluids, 2014, 55(5):1-14.[7]李晓俊.离小泵叶片前缘空化非定常流动机理及动力学特性研究[D].镇江:江苏大学,2013.[8]GUO X M, ZHU L, ZHU Z C, et al. Numerical and experimental investigations on the cavitation characteristics of a high-speed centrifugal pump with a splitter-blade inducer[J]. Journal of mechanical science & technology, 2015, 29(1):259-267.[9]郭晓梅,朱祖超,崔宝玲,等.诱导轮长短叶片位置对高速离心泵汽蚀性能的影响[J].工程热物理学报,2012,33(10):1695-1698. GUO Xiaomei, ZHU Zuchao, CUI Baoling, et al. Inducer-short blade position influence on cavitation performance of high speed centrifugal pump[J].Journal of engineering thermophysics, 2012,33(10):1695-1698.(in Chinese)[10]郭晓梅,李昳,崔宝玲,等.前置不同诱导轮高速离心泵旋转空化特性研究[J].航空学报,2013,34(7):1572-1581. GUO Xiaomei, LI Yi, CUI Baoling, et al. Research on the rotation cavitation performance of high-speed rotation centrifugal pump with different pre-positioned inducer[J]. Acta aeronautica et astronautica sinica, 2013,34(7):1572-1581.(in Chinese)[11]LI W G. An experimental study on the effect of oil viscosity and wear-ring clearance on the performance of an industrial centrifugal pump[J]. Journal of fluids engineering, 2012, 134(1):93-108.[12]赵伟国,邬国秀,黎义斌,等. 口环间隙变化对离心泵性能的影响研究[J]. 水力发电学报,2014,33(5):211-215. ZHAO Weiguo, WU Guoxiu, LI Yibin, et al. Study on effects of wear-rings clearance modifications on performance of centrifugal pump[J]. Journal of hydroelectric engineering, 2014,33(5):211-215.(in Chinese)[13]黄先北,刘竹青,杨魏. 离心泵口环间隙附近的空化特性研究[J].农业机械学报,2015,46(2):59-63. HUANG Xianbei, LIU Zhuqing, YANG Wei. Cavitation characteristics of centrifugal pump near wear-ring clearance[J].Transactions of the CSAM, 2015,46(2):59-63.(in Chinese)[14]王福军.计算流体动力学分析[M].北京:清华大学出版社,2004.[15]常书平,王永生. 基于CFD的混流泵空化特性研究[J]. 排灌机械工程学报,2012,30(2):171-175. CHANG Shuping, WANG Yongsheng. Cavitation performance research of mixed-flow pump based on CFD[J]. Journal of drainage and irrigation machinery engineering, 2012, 30(2): 171-175.(in Chinese)[16]关醒凡.现代泵理论与设计[M].北京:中国宇航出版社,2011.[17]何立东,叶小强,霍耿磊. 叶尖密封流场的细观特性对叶轮机械性能的影响[J]. 润滑与密封,2006(4):171-174. HE Lidong, YE Xiaoqiang, HUO Genglei. The influence of mesoscopic characteristic of tip seal flow field on turbomachinery[J].Lubrication engineering,2006(4):171-174.(in Chinese)[18]潘中永,袁寿其. 泵空化基础[M].镇江:江苏大学出版社,2013.[19]FU Y, YUAN J, YUAN S, et al. Numerical and experimental analysis of flow phenomena in a centrifugal pump operating under low flow rates[J]. Journal of fluids engineering, 2014, 137(1):205-207.
