含气介质用机械密封端面两相流动特性  

Two-phase Flow Characteristics of Mechanical Seals for Gas-containing Media

作　　者：张家祥 沈宗沼 高畅 张金亚[1] ZHANG Jiaxiang;SHEN Zongzhao;GAO Chang;ZHANG Jinya(College of Mechanical and Transportation Engineering,China University of Petroleum,Beijing 102249,China;Hefei General Machinery Research Institute,Hefei Anhui 230031,China)

机构地区：[1]中国石油大学(北京)机械与储运工程学院,北京102249 [2]合肥通用机械研究院有限公司,安徽合肥230031

出　　处：《润滑与密封》2022年第8期33-40,共8页Lubrication Engineering

基　　金：国家重点研发计划项目(2020YFB2010002)。

摘　　要：气液混输条件下,密封腔内的含气率较高将会使得密封液膜中有气体进入,从而导致密封环出现“失稳”现象。为探讨含气介质对机械密封性能的影响,通过建立端面螺旋槽型液膜模型,基于Mixture多相流模型,对端面液膜中气液两相分布及机械密封密封性能进行研究。结果表明:液膜内气相体积分数随气泡直径的减小而增大;不同入口含气率下密封端面两相分布规律相近,含气率较高的位置出现在槽根半径处;随着含气率、转速、压差的升高,槽根处的压力随之升高,从而影响密封性能;在相同含气率、转速及压差下,随膜厚的增加,泄漏量增大,开启力减小,且较小的膜厚对工况参数的改变更为敏感,槽深与膜厚的相关性较强,优化机械密封结构时需综合考虑两者的影响。Under the condition of gas-liquid mixed transportation,the high gas content in the sealing cavity will cause the gas to enter the sealing liquid film,resulting in the“instability”phenomenon of the sealing ring.In order to explore the influence of gas-containing medium on the performance of mechanical seal,based on the Mixture multiphase flow model,the gas-liquid two-phase distribution in the end surface liquid film and sealing performance of mechanical seal were studied by establishing the spiral groove liquid film model on the end surface.The results show that the gas volume fraction in the liquid film increases with the decrease of the bubble diameter.The two-phase distribution law of the seal end face is similar under different inlet gas content,and there exists higher gas content appears at the groove root radius.With the increase of void fraction,rotation speed,and pressure difference,the pressure at the root of the groove increases,which affects the sealing performance.Under the same void fraction,rotation speed and pressure difference,with the increase of film thickness,the leakage increases and the opening force decreases,and the smaller film thickness is more sensitive to the change of working condition parameters.The groove depth has a stronger correlation with the film thickness,both effects should be considered comprehensively when optimizing the structure of mechanical seal.

关 键 词：气液混输 机械密封 气液两相分布 密封性能 

分 类 号：TB42[一般工业技术]