分部式多孔质T型槽机械密封耦合模型与性能分析  

Coupling Model and Performance Analysis of Partial Porous T-Grooved Mechanical Seal

作　　者：李学萍 孟祥铠 韩丽云 赵文静 彭旭东 LI Xueping;MENG Xiangkai;HAN Liyun;ZHAO Wenjing;PENG Xudong(Institute of Chemical Process Machinery,Zhejiang University of Technology,Zhejiang Hangzhou 310032,China)

机构地区：[1]浙江工业大学化工机械设计研究所,浙江杭州310032

出　　处：《摩擦学学报(中英文)》2025年第2期242-252,共11页Tribology

基　　金：国家自然科学基金项目(52175193);叶企孙科学基金项目(U2241246)资助.

摘　　要：为提高液体密封的开启力和降低端面磨损,将多孔质与T型流体动压槽相结合,提出了1种分部式多孔质T型槽机械密封结构(PPT-MS),考虑多孔质内流体渗流力学与密封端面液膜润滑力学间的耦合作用,建立了分部式多孔质T型槽机械密封的数值模型,采用有限单元法求解考虑液膜空化的Reynolds方程和渗流力学方程.研究了多孔质的渗透率和几何参数对密封性能的影响规律,揭示了PPT-MS的密封机理,对比分析了不同转速和密封压力下普通T型槽机械密封与PPT机械密封的密封性能.结果表明:在T型槽的逆风侧会产生低压区,多孔质放置在低压区具有空化抽吸作用,可将密封介质引入密封间隙,起到增大液膜开启力和强化润滑的作用;随着多孔质渗透率的增大,PPT机械密封的开启力增大,摩擦系数减小,同时泄漏率也会有一定的增加,综合考虑渗透率在1×10^(-14)~5×10^(-14)m^(2)较为合适;当多孔质周向宽度占T型槽周向槽区宽度一半时PPT机械密封的开启力最大.研究结果可为多孔质机械密封的设计提供参考.Low viscosity liquid(such as liquid hydrogen,liquid oxygen,liquid methane,etc)as the sealing medium of the mechanical seal has difficult film formation and heavy wear problems.Numerous studies have shown that the application of various modifications such as micro-channels,compartments,micro-pores,texturing in mechanical noncontacting seals causes changes of hydrodynamic of the medium layer.To increase the film formation rate of dynamic pressure seals and reduce end face friction,apartial porous T-grooved mechanical seal(PPT-MS)is proposed by introducing porous materials into T-grooved mechanical face seals.Due to the existence of porous material,PPT mechanical seal in the working process both the sealing medium flow in the sealing gap,but also the sealing medium seepage in the porous material.The seepage characteristics of the sealing medium within the porous mass have an important influence on the lubrication performance of the liquid film.For exploring the influence of seepage and film pressure on the liquid film lubrication performance of mechanical seal,a mathematical model of PPT-MS is developed by considering the coupling effect between the fluid seepage mechanics of porous matrix and the hydrodynamic lubrication mechanics of fluid film.Taking the cavitation of fluid film into consideration,the seepage equation and the Reynolds equation are solved by using finite element method.The calculated results of this method are in good agreement with the numerical results and experimental data in the literature,which proves the feasibility of this method.The pressure distribution and the density ratio distribution of the PPT-MS,conventional T-Groove mechanical seal(TMS)and porous T-Groove mechanical seal(PT-MS)were compared.The effect of permeability and geometrical parameters of porous matrix on sealing performance are investigated and the sealing mechanism of the PPT-MS was revealed.In addition,the opening force of film was investigated simply for different T-groove geometric parameters such as the groove depth,th

关 键 词：密封性能 多孔质 T型槽 渗透率 空化 

分 类 号：TH117.2[机械工程—机械设计及理论]