双吸泵的汽蚀及扬程下降机理数值分析  

Numerical analysis of cavitation and head drop of a double-suction pump

作　　者：张彩凤 苏永升[1] ZHANG Cai-feng;SU Yong-sheng(Key Lab of Pressurized Systems and Safety,Ministry of Education, East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]华东理工大学承压系统与安全教育部重点实验室,上海200237

出　　处：《南水北调与水利科技》2017年第A02期200-204,共5页South-to-North Water Transfers and Water Science & Technology

摘　　要：用CFX软件对一台单级双吸离心泵的汽蚀问题,从叶轮子午面和叶片两个角度对汽蚀空泡的发展过程进行了分析,并研究了不同进口压力时的流体流线变化规律。研究结果表明,设计流量时空泡最先出现在叶片吸力面前缘靠近前盖板处,前盖板的汽蚀程度大于后盖板,当吸水室进口处压力逐渐减小时,空泡区沿着流体流动方向不断迁移和扩大。当汽蚀较为严重时,空泡所占比例增大,导致液体边界层的分离,从而在流道中产生漩涡,漩涡引起的能量损失是引起扬程下降的主要原因。In this paper,the cavitation performance and head drop of a double-suction pump are numerically analyzed.Distribution of vapor in the impeller meridian plane,blades and streamline distribution are presented and analyzed.Research results show that the vacuoles appeared first in the leading edge of the blade suction surface near the rear,front cover plate of the cavitation degree is greater than that of the rear cover.Along with the decreasing of the inlet pressure,the bubble zone is moved and expanded along the direction of the blade to the outlet.When the cavitation development to a certain extent,the flow of the liquid in the flow passage inside the boundary layer separation of the liquid to produce a vortex,the vortex loss is the main reason for the head drop.

关 键 词：双吸泵 空泡分布 扬程下降 数值模拟 

分 类 号：TH317[机械工程—机械制造及自动化]