Numerical analysis for effects of different blade tip clearance on performance in mixed-flow pump

doi:10.3969/j.issn.1002-6819.2014.23.012

CORC > 兰州理工大学 > 兰州理工大学 > 新能源学院

	Numerical analysis for effects of different blade tip clearance on performance in mixed-flow pump
	Li, Yibin 1,2; Hu, Penglin 2; Li, Rennian 1,2; Li, Penghui 3; Bi, Zhen 2
刊名	Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
	2014-12-01
卷号	30 期号:23 页码:86-93
关键词	Efficiency Flow fields Flow measurement Flow velocity Friction Impellers Numerical analysis Pumps Stream flow Turbulence models Velocity Velocity distribution External characteristic Frictional resistance K-Omega turbulence model Leakage flow Mixed flow pump Performance prediction Tip clearance Topological structure
ISSN号	10026819
DOI	10.3969/j.issn.1002-6819.2014.23.012
英文摘要	The mixed-flow pump has some good characteristics, such as high efficiency, good start performance, and wide working condition. The traditional design methods of mixed-flow pumps cannot evaluate the sensitivity of the tip clearance's impact on pump performance quantificationally. In order to reveal the tip clearance effect on the internal flow field and the performance of mixed-flow pump, and given the selection range of blade tip clearance, four mixed-flow pumps with different tip clearance values, 0, 0.5, 1.0, and 1.5 mm, respectively, were studied. The distorted triangle method was adopted to design the impeller and guide vane, and based on the software ICEM CFD to generate block hexahedron structured grids of the computational domain, and then the topological structure of the grids of the blade tip region was optimized. The internal flow field of the pumps was simulated based on the SST k-ω turbulence model and SIMPLEC algorithm, using the structured grid technology mentioned above, and the numerical simulation results were compared with the test experimental data, which agreed well with each other. The results show that the value of tip clearance have a significant effect on mixed-flow pump hydraulic performance, when tip clearance was 0.5 mm. The head-flow positive slope characteristic of the pump can be suppressed effectively, and the efficiency value of mixed-flow pump is highest at this time; when tip clearance was 0, the pump head-flow positive slope characteristic is relatively obvious; when tip clearance was 1mm, simulation values and experimental values matched well, so the SST k-ω model can simulate the flow characteristics of tip clearance of mixed-flow pumps well, so that the results of the performance prediction have some credibility. Under small flow conditions, small tip clearance values can restrain unstable positive slope features of mixed-flow pump. When tip clearance was 0.5mm, the performance of the pump with small tip clearance is the best. With the increasing of tip clearance value, tip leakage flow became outstanding gradually, the axis plane flow velocity of the near wall region of the impeller outlet and the vorticity change significantly, which indicates that tip clearance affects the axis plane velocity distributions of the impeller and the load distributions of the blades directly. As influenced by the frictional resistance and the viscous resistance of the wall, the impeller axis plane flow velocity of the impeller hub region and tip clearances areas is relatively small. When tip clearance increase, blades load of the impeller hub region and tip clearances areas decay rapidly, and it affects the performance ability of impeller blades. At the same time, serious mix permeability and entrainment effects come into being between the leakage flow near the blade tip and the main stream flow, and cause the significant decline in the axis plane flow velocity in the region near the blade tip of impeller outlet. At the moment, the jet effect of the tip leakage flow decays gradually, and the sphere of influence gradually extends to the entire blade tip region. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
语种	中文
出版者	Chinese Society of Agricultural Engineering
内容类型	期刊论文
源URL	[http://ir.lut.edu.cn/handle/2XXMBERH/113682]
专题	新能源学院兰州理工大学能源与动力工程学院
作者单位	1.Key Laboratory of Fluid machinery and Systems, Lanzhou; Gansu Province; 730050, China; 2.School of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou; 730050, China; 3.Hunan XEMG Changsha Pump Works Co., Ltd., Changsha; 410205, China
推荐引用方式 GB/T 7714	Li, Yibin,Hu, Penglin,Li, Rennian,et al. Numerical analysis for effects of different blade tip clearance on performance in mixed-flow pump[J]. Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering,2014,30(23):86-93.
APA	Li, Yibin,Hu, Penglin,Li, Rennian,Li, Penghui,&Bi, Zhen.(2014).Numerical analysis for effects of different blade tip clearance on performance in mixed-flow pump.Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering,30(23),86-93.
MLA	Li, Yibin,et al."Numerical analysis for effects of different blade tip clearance on performance in mixed-flow pump".Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering 30.23(2014):86-93.