叶顶间隙对低比转数小流量泵性能的影响  

Effect of Tip Clearance on Low Specific Speed and Low Flow Pump Performance

作　　者：郝开元[1] 安东森 HAO Kai-yuan;AN Dong-sen(Beijing Aerospace Propulsion Institute,Beijing 100076)

机构地区：[1]北京航天动力研究所,北京100076

出　　处：《液压与气动》2024年第1期108-114,共7页Chinese Hydraulics & Pneumatics

基　　金：中国航天科技集团六院自主研发项目(010003000100060070)。

摘　　要：为建立叶顶间隙对低比转速小流量泵性能的影响关系,采用数值计算的方法,以叶顶间隙宽s和叶轮出口宽b的比值(s/b)表征间隙大小,对不同间隙下泵的性能展开对比分析。分析发现,随着间隙的增加,泵的扬程和效率均逐渐降低,最大和最小间隙下的扬程和效率差分别达15.4%,5.5%。当间隙较小即s/b<0.2时,扬程曲线在小流量工况会出现不稳定的“驼峰”现象,在s/b>0.3后,设计工况附近效率的降幅显著增大。从流动特性来看,随着叶顶间隙的增大,间隙泄漏流对叶轮内主流区影响加剧,会诱导严重的二次流和旋涡的产生,同时间隙内不稳定流动也会产生能量损失,造成扬程和效率下降。为低比转数小流量泵的设计与优化提供借鉴意义。To establish the relationship between tip clearance and performance of low specific speed small flow pumps.By means of numerical calculation,the gap size is characterized by tip clearance width“s”and impeller outlet width“b”ratio,and the pump characteristics under different clearances are compared.With the increase of clearance,pump head and efficiency gradually decrease.Difference of head and efficiency under the maximum and minimum clearance is 15.4%and 5.5%respectively.When the clearance is small(s/b<0.2),unstable“hump”phenomenon will occur in the head curve under small flow conditions.After s/b>0.3,the efficiency reduction near the design conditions will increase significantly.In terms of flow characteristics,the increase of tip clearance will result in clearance flow affecting impeller flow more seriously,leading to severe secondary flow and vortex.Meanwhile,unstable flow within tip clearance can also cause energy loss.Finally,head and efficiency are decrease.The study provides a reference for the design and optimization of low specific speed small flow pump.

关 键 词：离心泵 叶顶间隙 低比转数 小流量 

分 类 号：TH137[机械工程—机械制造及自动化] TH311