叶顶间隙对离心泵气液两相流特性的影响  

Effect of Blade Tip Clearance on Gas-liquid Two-phase Flow Characteristics for Centrifugal Pumps

作　　者：田龙 杨军虎[1] 余学民 徐国斌 李松源 YANG Jun-hu;TIAN Long;YU Xue-min;XU Guo-bin;LI Song-yuan(College of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学能源与动力工程学院,甘肃兰州730050

出　　处：《液压气动与密封》2023年第5期88-93,共6页Hydraulics Pneumatics & Seals

基　　金：国家自然科学基金(51979135,51469014)。

摘　　要：为研究叶顶间隙对离心泵气液两相流特性的影响,以比转速为33的半开式叶轮离心泵为研究对象,设计了四种叶顶间隙值(0.3 mm、0.5 mm、0.7 mm、1 mm)的模型泵,采用Eulerian模型对各间隙值模型泵进行了不同进口含气率(IGVF)不同流量工况下气液两相流动进行了数值计算,得到了不同IGVF下各模型泵的外特性曲线,并分析了叶顶间隙变化对模型泵外特性及其内部流场影响规律。结果表明:当IGVF≤5%时,气相在泵内的聚集程度较低,叶顶间隙泄漏流动是影响模型泵性能的主要原因,模型泵的性能随间隙值的增大而减小,0.3 mm间隙值为最佳间隙值;当IGVF=12%时,气相在泵内高度聚集,导致叶轮内部流动极为紊乱,湍动能的分布范围和强度也逐渐增强,由此造成的能量损失是导致模型泵性能下降的主要因素,其中0.5 mm间隙值模型泵的湍动能分布和强度最小,此时模型泵的性能达到最佳。In order to study the influence of blade tip clearance on the gas-liquid two-phase flow characteristics of centrifugal pump,a semi-open impeller centrifugal pump with a specific speed of 33 was used as the research object,and Designed 4 types of model pumps with 0.3 mm,0.5 mm,0.7 mm and 1 mm clearance values,and adopted Eulerian model for each model pump with different inlet gas content rate(IGVF)and different flow rates.The external characteristic curves of the model pumps with different IGVF were obtained,and the influence of the variation of the blade tp clearance on the external characteristics and the internal flow field of the model pumps was analyzed.The results show that:when IGVF≤5%,the degree of gas phase accumulation in the pump is low,and the leakage flow at the blade tip clearance is the main reason to affect the performance of the model pump,and the performance of the model pump decreases with the increase of the blade tip clearance value,and 0.3 mm clearance value is the best clearance value;when IGVF=12%,the gas phase accumulates highly in the pump,which leads to the extremely turbulent flow inside the impeller,and the distribution range and intensity of turbulent kinetic energy are gradually enhanced,the resulting energy loss is the main factor leading to the degradation of the model pump performance,where the turbulent kinetic energy distribution and intensity of the model pump with 0.5 mm clearance value is the smallest,and the performance of the model pump reaches the best at this time.

关 键 词：离心泵 叶顶间隙 气液两相流 数值模拟 

分 类 号：TH137[机械工程—机械制造及自动化] TH311