离心泵内诱导轮与叶轮轴向相对位置的探讨  

Study on axial spacings between inducer and impeller of centrifugal pump

作　　者：卢金玲[1] 邓佳[1,2] 徐益荣[3] 冯建军[1] 罗兴锜[1] 

机构地区：[1]西安理工大学水利水电学院,西安710048 [2]西安热工研究院有限公司,西安710054 [3]乌海电业局,内蒙古乌海016000

出　　处：《水力发电学报》2015年第8期91-96,共6页Journal of Hydroelectric Engineering

基　　金：国家自然科学基金项目(51279160);陕西省教育厅专项科研计划(11JK0731);教育部博士点基金(20126118130002);陕西省百人计划(2012)

摘　　要：离心泵内诱导轮与叶轮的轴向相对位置会对叶轮内的流动产生影响,从而影响整台泵的性能。为研究诱导轮相对叶轮不同轴向位置下离心泵内部的不稳定流动特性及其对离心泵水力性能的影响,本文以某单级离心泵为研究对象,采用数值模拟方法初步探讨了诱导轮相对于叶轮在三种不同轴向位置下离心泵的内部流动特性,分析了其外部特性、叶轮所受的径向力、水压脉动特性及空化特性等。结果表明,针对本文研究的三种轴向位置而言,离心泵的扬程和效率随诱导轮和叶轮间轴向距离的增大逐渐提高,扬程的最大值较最小值增幅达1.8%,效率变化达4.3%;诱导轮和叶轮间的轴向相对位置对叶轮和径向导叶间的相互干涉有影响,从而影响叶轮所受径向力的大小和方向;轴向距离从0.05D1增加到0.1D1时,离心泵的空化性能明显提高;从0.1D1增加到0.15D1时,空化性能变差;改变轴向位置直接影响叶轮进口压力脉动特性。The axial spacing between the inducer and impeller of a centrifugal pump influences the flow in the impeller section and the pump performance. To study these influences, we have numerically simulated the unsteady flows in a single-stage centrifugal pump with its pre-inducer and impeller installed at three different axial spacings, and analyzed the external characteristics, radial force on impeller, pressure fluctuations, and cavitation characteristics. Results show that in the range of the axial spacings examined, an increase in spacing leads to an increase in working head and efficiency, with the maximum variations being 1.8% and 4,3% respectively. Variation in the axial spacing modifies the interaction between the impeller and guide vanes, and thus it can influence the magnitude and direction of the radial force on the impeller to some extent. For cavitation performance, an increase in the spacing from 0.05D1 to 0.1D1 results in a significant improvement, while a further increase up to 0.15D1 shows a negative effect. In addition, the frequency and amplitude in pressure fluctuations at the impeller inlet is affected directly.

关 键 词：离心泵 诱导轮 叶轮 轴向位置 

分 类 号：TH311[机械工程—机械制造及自动化]