排灌机械工程学报2018，Vol.36Issue(5)：377-383,7.DOI:10.3969/j.issn.1674-8530.16.0278
超低比转数离心泵的内部流动及非定常特性
Internal flow and analysis of its unsteady characteristics in centrifugal pump with ultra-low specific-speed
摘要
Abstract
In order to explore internal flow and its unsteady characteristics in ultra-low specific-speed centrifugal pumps more comprehensively,an ultra-low specific-speed centrifugal pump with a specificspeed ns =25 was chosen as a study object.Then numerical simulations of the unsteady three-dimensional fluid flow in the pump were carried out.Finally,the internal flow field,radial thrust on the impeller and the pressure fluctuation of fluid in each section of the volute were analyzed.The results show that there appears vortices in various sizes and numbers in flow channels of the impeller under different flow conditions.A high velocity zone is found in two adjacent channels near the tongue,however,the zone disappears gradually with the increase of flow rate.Under high flow rate conditions,the area of the low velocity zone decreases gradually,the size and number of vortices reduce steadily,and the relative velocity distribution in the impeller becomes uniform gradually.The orientation and magnitude of radial thrust on the impeller vary constantly,showing a hexagram pattern.The amplitude of radial thrust decreases gradually with increasing flow rate,but its main excitation frequencies are all the blade passing frequency or its integer multiples.The peak pressure fluctuation in each section of the volute decreases along the flow path and the main excitation frequencies are all the blade passing frequency or its integer multiples.This fact suggests that the impeller-volute interaction is one major factor influencing pressure fluctuation in the volute.These results have provided useful reference for optimum design of the ultra-low specific-speed centrifugal pump and selection of its feasible operating flow rate range.关键词
超低比转数离心泵/内流模拟/径向力/压力脉动Key words
ultra-low specific-speed centrifugal pump/internal flow simulation/radial force/pressure fluctuation分类
农业科技引用本文复制引用
陈杰,王勇,刘厚林,邵昌,张翔..超低比转数离心泵的内部流动及非定常特性[J].排灌机械工程学报,2018,36(5):377-383,7.基金项目
国家自然科学基金资助项目(51309120) （51309120）
江苏省产学研联合创新资金-前瞻性联合研究项目(BY2015064-10) （BY2015064-10）
江苏高校优势学科建设工程项目 （）
流体及动力机械教育部重点实验室(西华大学)开放课题(szjj2016-068) （西华大学）
