摘要
针对液环泵内易发生的气体过压缩现象,采用VOF两相流模型对液环泵压缩机工况下的内部气液两相流动进行数值模拟,研究排气口前端单向阀的开启对液环泵流动结构及性能的影响,分析不同压缩比工况下泵内的压力分布以及相态分布等规律。结果表明,随着液环泵排气口压力的降低,液环泵排气口前端容易发生过压缩现象,过压缩现象会导致液环泵的功率损失增大,降低液环泵的效率。排出口压力越低,则过压缩现象越严重。在低压缩比工况下排气口前端的单向阀在压差的作用下自动开启,可以有效地避免发生过压缩现象,提升液环泵的效率及吸气量。为分析排气口前端单向阀面积变化规律对液环泵性能的影响,在原始设计的基础上提出三种不同面积变化规律的单向阀布置,对比分析发现,低压缩比工况下适当增大排气口前端单向阀的面积可以有效地提高液环泵的吸气量,降低阀孔流速,提升液环泵的性能。
Concerning the gas over-compression phenomenon which is easily occur in liquid ring pump,the VOF two-phase flow model was used to simulate the internal gas liquid two-phase flow in liquid-ring pump at compressor conditions.The effects that opening of exhaust check valve on the flow structure and hydraulic performance of liquid-ring pump was investigated,and the pressure and phase distribution of pump inner flow under different compression ratio was analyzed.The results show that the over-compression phenomenon is easily occur in the front of exhaust with the decrease of outlet pressure,which would lead the increasing the energy consumption and decreasing of pump efficiency.The over-compression phenomenon aggravates with the decrease of outlet pressure.Under lower compression ratio condition,the exhaust check valve would open automatically with the action of pressure difference,which can effectively avoid the over-compression phenomenon,and improve the efficiency and suction capacity of the liquid ring pump.To analyze the effects of the exhaust check valve area on the performance of liquid ring pump,three kinds of check valve arrangement with different area were proposed on the basis of original design.The analysis results show that under the lower compression ratio condition,the larger area of check valve can effectively increase the suction capacity of liquid ring pump,reduce the velocity of the valve,and enhance the performance of pump.
作者
张人会
蒋利杰
郭广强
孙鹏程
孟凡瑞
ZHANG Ren-Hui;JIANG Li-Jie;GUO Guang-Qiang;SUN Peng-Cheng;MENG Fan-Rui(College of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou 730050,China;Key Laboratory of Fluid Machinery and Systems,Gansu Province,Lanzhou University of Technology,Lanzhou 730050,China;Zibo Water Ring Vacuum Pump Factory Co.,LTD,Zibo 255200,China)
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2020年第7期1673-1678,共6页
Journal of Engineering Thermophysics
基金
国家重点研发计划项目(No.2016YFB0200901)
国家自然科学基金项目(No.51979135,51469014)
甘肃省陇原创新人才计划项目。
关键词
过压缩
气液两相流
液环泵
单向阀
over-compression
gas-liquid flow
liquid ring pump
check valve
