Analysis of inner flow field and its hydraulic performance of liquid-ring pump with splitter blades

doi:10.11975/j.issn.1002-6819.2021.04.015

	Analysis of inner flow field and its hydraulic performance of liquid-ring pump with splitter blades
	Zhang, Renhui 1,2; Li, Ruiqing 1; Zhang, Jingxian 1
刊名	Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
	2021-02-15
卷号	37 期号:4 页码:122-129
关键词	Flow measurement Impellers Liquids Spectrum analysis Structural design Wakes Well pumps Blade passing frequency Compression regions Gas-liquid interface Geometric asymmetries Hydraulic performance Inhomogeneous distribution Pressure fluctuation Transition regions
ISSN号	10026819
DOI	10.11975/j.issn.1002-6819.2021.04.015
英文摘要	Splitter blades were introduced to the structural design of a liquid ring pump, as they could suppress the impeller outlet wake and pressure pulsation. Taking a prototype of a 2BEA203 liquid ring pump as a research object, this study aims to analyze the influence of the splitter blades on the inner flow and the hydraulic performance of a liquid ring pump. In the design of splitter blades, the inlet diameter of the short blade was set as 0.65 times that of the long blade, considering the expelling coefficient of blades. The specific blades included 14 long blades and 14 short ones. The profile and width of the short blade were designed exactly the same as those of the long blade, because of the asymmetry of flow in the suction and exhaust regions. A numerical simulation combined with an experimental test was conducted to compare the inner flow and hydraulic performance of the prototype pump with those of the liquid ring pump with splitter blades. The results show that the gas-liquid interface in the liquid ring pump with splitter blade was smoother than that in the prototype pump. The pressure was lower at the casing of the exhaust region and the compression region in the liquid-ring pump than that in the prototype pump. The intensity of the secondary flow vortex reduced in the impeller channel, and the velocity decreased in the high-speed area near the exhaust region of the liquid ring pump. The efficiency increased by 2.7, 3.8, and 4.3 percent points in the liquid ring pump with splitter blades at the conditions of 0.02, 0.035, and 0.05 kg/s, respectively, compared with the prototype impeller liquid ring pump. The vacuum of the pump inlet also slightly increased. There were obvious partition features of pressure pulsation along the circumference, where existed an inhomogeneous distribution of the volume fraction in the flow passage of impeller, due mainly to the geometric asymmetry of the impeller and pump casing along the circumference. Four parts were divided for the monitoring positions on the pump casing, according to the spectrum features of pressure fluctuation. The intensity of wake near the impeller outlet was strong from the transition to the beginning regions of the suction, because the width of the liquid ring in the impeller was larger, where the main frequency of pressure pulsation was Blade Passing Frequency (BPF) in this region. Near the end region of suction, the short blades posed little effect on the main frequency of pressure pulsation because the liquid ring was thinner and the outlet wake was weak. In this case, the main frequencies of pressure pulsation were the long blade BPF and shaft frequency for the liquid ring pump with splitter blades and the liquid ring pump with prototype impeller, respectively. In the compression region, the main frequency of pressure pulsation was shaft frequency in the liquid ring pump, because the outlet wake was the weakest. In the exhaust and transition region, the main frequencies of pressure pulsation were the long blade BPF and BPF in the liquid ring pump with splitter blades and the liquid ring pump with prototype impeller, respectively. The reason was that the thickness of the liquid ring in the impeller was increasing gradually again. The amplitude of pressure pulsation decreased first in the liquid ring pump casing from the suction region, and then reached the minimum in the compression region, and finally increased again in the exhaust region. Furthermore, the amplitude of pressure pulsation was basically lower in the casing of the liquid ring pump with a splitter blade than that in the prototype impeller. © 2021, Editorial Department of the Transactions of the 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/150917]
专题	能源与动力工程学院
作者单位	1.College of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou; 730050, China; 2.State Key Laboratory of Gansu Fluid Machinery and Systems, Lanzhou; 730050, China
推荐引用方式 GB/T 7714	Zhang, Renhui,Li, Ruiqing,Zhang, Jingxian. Analysis of inner flow field and its hydraulic performance of liquid-ring pump with splitter blades[J]. Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering,2021,37(4):122-129.
APA	Zhang, Renhui,Li, Ruiqing,&Zhang, Jingxian.(2021).Analysis of inner flow field and its hydraulic performance of liquid-ring pump with splitter blades.Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering,37(4),122-129.
MLA	Zhang, Renhui,et al."Analysis of inner flow field and its hydraulic performance of liquid-ring pump with splitter blades".Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering 37.4(2021):122-129.