液环泵复合叶轮内流场及外特性分析  

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

作　　者：张人会[1,2] 李瑞卿 张敬贤 Zhang Renhui;Li Ruiqing;Zhang Jingxian(College of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou 730050,China;State Key Laboratory of Gansu Fluid Machinery and Systems,Lanzhou 730050,China)

机构地区：[1]兰州理工大学能源与动力工程学院,兰州730050 [2]甘肃省流体机械及系统重点实验室,兰州730050

出　　处：《农业工程学报》2021年第4期122-129,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金资助项目(51979135)。

摘　　要：为分析复合叶轮液环泵的内流场及外特性,以2BEA203型液环泵为基础,综合考虑液环泵叶轮及复合叶轮设计原理,设计了液环泵复合叶轮,并采用数值模拟与试验测试相结合的方法对原型叶轮液环泵和复合叶轮液环泵内瞬态流场进行对比分析。结果表明:相对于原型叶轮液环泵,复合叶轮液环泵内气液分界面更加光滑,排气区及压缩区壳体处压力分布均有所降低,叶轮流道内二次流旋涡强度减弱。2BEA203型液环泵复合叶轮在0.02、0.035和0.05kg/s流量工况下的效率分别提升了2.7、3.8和4.3个百分点,各工况下的真空度也略有提高。由于流动的非对称特性,复合叶轮和原型叶轮液环泵壳体内压力脉动沿周向均呈现出明显的分区特性。液环泵壳体从吸气区开始沿圆周方向的压力脉动幅值先变小,在压缩区达到最小而后再变大;复合叶轮液环泵壳体绝大部分监测点处压力脉动幅值小于原型叶轮;液环泵壳体各分区的压力脉动呈现不同的主频特征。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 2 BEA203 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 fe

关 键 词：液环泵 压力脉动 内流场 复合叶轮 分区特性 

分 类 号：TK730[交通运输工程—轮机工程]