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| Numerical analysis of effect of blade tip clearance on pressure fluctuation in mixed-flow pump inlet |
| Li Rennian1,2, Hu Penglin1, Li Yibin1,2, Bi Zhen1, Zhou Dong3 |
| 1.School of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou, Gansu 730050, China; 2.Key Laboratory of Fluid Machinery and Systems, Gansu Province, Lanzhou, Gansu 730050, China; 3.Hunan XEMG Changsha Pump Works Co.Ltd., Changsha, Hunan 410205, China |
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Abstract Because of considerable influence of blade tip clea-rance on performance and flow in a mixed-flow pump, a proper selection of the clearance is important in the design of the pump. In order to identify the effects of the blade tip clearance on the pressure fluctuation characteristics in a mixed-flow pump inlet, the unsteady, three-dimensional turbulent flows in the pump are simulated at 0, 0.5, 1.0, 1.5 mm clearances, based on the SST k-ω turbulence model and large eddy simulation(LES)approach. Also, the SIMPLEC algorithm and block structured grids are adopted. The simulations are conducted at low flow rates, and the pressure fluctuation characteristics in the impeller inlet are monitored. The results show that with the increasing tip clearance the pump head decreases gradually. The tip clearance has a significant effect on the pressure fluctuation distribution along radius in the impeller inlet, the pressure fluctuation amplitude is smaller in the primary flow region in the impeller inlet, while it gets larger near the wall. The dominated pressure fluctuation frequencies at various tip clearances are the blade passing frequency, but the pressure fluctuation is quite different from one clearance to another. Specially, a larger tip clearance can reduce the pressure fluctuation amplitude. This can be in favour of improving the operational stability of the pump.
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Received: 10 October 2014
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| [1]王春林,杨晓勇,李长军,等.混流式主泵模型泵内部流场压力脉动特性研究[J].核动力工程,2013,34(4):47-52. Wang Chunlin, Yang Xiaoyong, Li Changjun, et al. Pressure fluctuation characteristics of flow field of mixed flow nuclear primary pump[J]. Nuclear Power Engineering, 2013,34(4):47-52.(in Chinese)[2]李伟,施卫东,张德胜,等.基于流固耦合方法的斜流泵叶轮强度分析[J].流体机械,2012,40(12):19-22. Li Wei,Shi Weidong,Zhang Desheng,et al. Strength analysis on impeller of mixed flow pump based on the fluid-structure interaction method[J]. Fluid Machinery, 2012, 40(12): 19-22.(in Chinese)[3]Kato C, Mukai H, Manabe A. Large-eddy simulation of unsteady flow in a mixed-flow pump[J]. International Journal of Rotating Machinery, 2003, 9(5):345-351.[4]仇宝云,林海江,黄季艳,等.大型立式轴流泵叶片进口流场及其对水泵影响研究[J].机械工程学报,2005, 41(4): 28-34. Qiu Baoyun, Lin Haijiang, Huang Jiyan, et al. Study on flow field in blade inlet of large vertical axial-flow pump and its influence on pump[J]. Chinese Journal of Mechanical Engineering, 2005, 41(4):28-34.(in Chinese)[5]黎耀军,沈金峰,严海军,等.叶顶间隙对轴流泵轮缘泄漏流动影响的大涡模拟[J].水利学报, 2014,45(2):235-242. Li Yaojun, Shen Jinfeng, Yan Haijun, et al. Investigation of the effects of tip-gap size on the tip-leakage flow in an axial-flow pump using LES[J]. Journal of Hydraulic Engineering,2014,45(2):235-242.(in Chinese)[6]王福军,张玲,张志民.轴流泵不稳定流场的压力脉动特性研究[J].水利学报, 2007, 38(8): 1003-1009. Wang Funjun, Zhang Ling, Zhang Zhimin. Analysis on pressure fluctuation of unsteady flow in axial flow pump [J]. Journal of Hydraulic Engineering,2007, 38(8):1003-1009.(in Chinese)[7]靳栓宝,王永生,常书平,等.混流泵内流场压力脉动特性研究[J].农业机械学报,2013,44(3):64-68. Jin Shuanbao, Wang Yongsheng, Chang Shuping, et al. Pressure fluctuation of interior flow in mixed-flow pump[J]. Transactions of the Chinese Society for Agricultural Machinery, 2013,44(3):64-68.(in Chinese)[8]张兆顺,崔桂香,许春晓.湍流大涡数值模拟的理论和应用[M].北京:清华大学出版社,2008.[9]张德胜,吴苏青,施卫东,等.不同湍流模型在轴流泵叶顶泄漏涡模拟中的应用与验证[J].农业工程学报, 2013,29(13): 46-53. Zhang Desheng, Wu Suqing, Shi Weidong, et al. Application and experiment of different turbulence models for simulating tip leakage vortex in axial flow pump[J]. Transactions of the CSAE, 2013, 29(13):46-53.(in Chinese)[10]施卫东,张华,陈斌,等.不同叶顶间隙下的轴流泵内部流场数值计算[J].排灌机械工程学报,2010,28(5):374-377. Shi Weidong, Zhang Hua, Chen Bin, et al. Numerical simulation of internal flow field in axial-flow pump with different blade tip clearance sizes[J].Journal of Drai-nage and Irrigation Machinery Engineering, 2010, 28(5):374-377.(in Chinese)[11]施卫东,姚捷,张德胜,等.采样频率和时间对轴流泵压力脉动特性的影响[J].排灌机械工程学报, 2013, 31(3):190-194. Shi Weidong, Yao Jie, Zhang Desheng, et al. Influence of sampling frequency and time on pressure fluctuation characteristics of axial flow pump[J]. Journal of Drai-nage and Irrigation Machinery Engineering, 2013, 31(3):190-194.(in Chinese) |
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