不同箔坝位置关系下浮动坝箔片端面气膜密封性能研究  

Performance of Floating Seal Dam Compliant Foil Face Gas Seal under Different Foil-Dam Positions

作　　者：陈源 熊聪 彭旭东[3] 李运堂 李孝禄 王冰清 金杰 CHEN Yuan;XIONG Cong;PENG Xudong;LI Yuntang;LI Xiaolu;WANG Bingqing;JIN Jie(College of Mechanical and Electrical Engineering,China JiLiang University,Zhejiang Hangzhou 310018,China;Key Laboratory of Intelligent Manufacturing Quality Big Data Tracing and Application of Zhejiang Province,China JiLiang University,Zhejiang Hangzhou 310018,China;College of Mechanical Engineering,Zhejiang University of Technology,Zhejiang Hangzhou 310032,China)

机构地区：[1]中国计量大学机电工程学院,浙江杭州310018 [2]中国计量大学浙江省智能制造质量大数据溯源与应用重点实验室,浙江杭州310018 [3]浙江工业大学机械工程学院,浙江杭州310032

出　　处：《摩擦学学报》2023年第5期481-491,共11页Tribology

基　　金：国家自然科学基金(51905513,52005470);浙江省高校基本科研业务费专项资金(2021YW07);浙江省博士后科学基金(ZJ2020084)资助。

摘　　要：提出一种具有浮动密封坝的箔片端面气膜密封(FSD-CFFGS),并以此为研究对象建立密封气弹耦合润滑理论模型,采用有限差分法求解可压缩气体的雷诺方程,分别在箔片端面高于、等于和低于密封坝平面三种关系下系统研究支撑箔柔度系数对膜压、形变及密封性能的影响规律,探究FSD-CFFGS的工作原理和密封机理.综合考虑自适应性、开启性和控漏性,确定FSD-CFFGS支撑箔柔度系数优选范围.结果表明:当箔片端面高于密封坝平面时,密封流体动压效应显著,开启性能较好;高度差Δh取1.5~2.5μm、箔片区支撑箔柔度系数α1取0.05~0.15、浮动坝区支撑箔柔度系数α2取10^(-5)~10^(-3)时,FSD-CFFGS具有一定自适应能力并能保证较好的开启性和控漏性.Dry gas seal is widely used in the shaft seal of middle and high speed rotating machinery.However,when the shaft vibrated violently or the working conditions change obviously,the dry gas seal is liable to failure due to the brittle solid structure of the sealing ring which is easy to be rubbed and crushed.Besides,it is poor in heat dissipation.Therefore,it is difficult to adapt to extreme working conditions such as ultra-high speed,high temperature and high vibration.In order to solve the above problems,this paper presented a new type of compliant foil face gas seal with floating seal dam(FSD-CFFGS)which was based on gas foil thrust bearings and existing compliant foil face gas seal structure.The bump foil was set at the bottom of the rigid seal dam.When the film thickness or the working conditions were changed by disturbance,the sealing performance and the anti-impact ability of seal dam could be improved by adaptive floating.In addition,the bottom hollow structure formed by the bump foil was conducive to the heat dissipation of the foil area and the floating seal dam area,and could effectively avoid the heat crack of the sealing ring caused by the high temperature.Taking this as the research object,the theoretical model of elasto-aerodynamically coupling was established.The steady Reynolds equation was discretized by the finite difference method.After that,the convergent film pressure,foil deformation and film thickness distribution were solved by numerical method.Exploring the working principle and sealing mechanism of FSD-CFFGS under three kinds of foil-dam positions:the position of foil plane was higher than,equal to and lower than the position of seal dam plane and then the influence of supporting foil compliance coefficient on the film pressure,deformation and sealing performance was systematically studied.Comparing the opening force,film stiffness,leakage rate and stiffness-leakage ratio under different supporting foil compliance coefficients.Self-adaptability,opening performance and leakage control perfo

关 键 词：弹性箔片 端面气膜密封 浮动密封坝 柔度系数 密封性能 

分 类 号：TH117.1[机械工程—机械设计及理论] TB42[一般工业技术]