基于半解析法的极端工况干气密封动态特性研究与参数设计  

Analysis and parametric design of the dynamics of a dry gas seal for extreme operating conditions using a semi-analytical method

作　　者：刘向锋[1] 徐辰[1] 黄伟峰[1] 

机构地区：[1]清华大学摩擦学国家重点实验室,北京100084

出　　处：《清华大学学报（自然科学版）》2014年第2期223-228,234,共7页Journal of Tsinghua University(Science and Technology)

基　　金：国家"九七三"重点基础研究项目(2012CB026003);国家科技重大专项项目(ZX06901)

摘　　要：采用Miller与Green提出的半解析方法,对极端工况下螺旋槽干气密封的动态特性进行了研究。首先运用有限元方法数值求解可压缩气体Reynolds方程,通过计算气膜对膜厚阶跃变化的响应,建立了干气密封中气膜的动刚度模型。在频域内将该模型应用于密封环的动力学分析,通过数学变换得到密封环在时域内的运动,从而建立了干气密封动态响应的解析式分析方法。利用该方法分析了干气密封对轴向、角向位移扰动的响应,并研究了密封端面几何参数对动态特性的影响规律。通过参数设计,可以得出端面参数的合理取值范围,从而改善密封动态性能。The dynamics of a spiral groove dry gas seal （DGS） are analyzed using extreme operating conditions based on the semi-analytical method developed by Miller and Green. The compressible form of the Reynolds equation is solved numerically with a finite element method for the DGS gas film model to determine the stiffness model for the gas film during the dynamic process by calculating the gas film response to a step jump in the film thickness. Then, the stiffness model is applied to the kinetic model of the seal ring in the frequency domain. The movement of the seal ring in the time domain is obtained by an inverse Laplace transform. The method is used to solve for the transient response of a DGS to both the axial and tilt initial disturbances. The influences of the geometric parameters are evaluated to find reasonable parameters for parametric design to improve dynamic performance of the DGS for turbine compressor spiral groove DGS designs.

关 键 词：干气密封(DGS) 动态特性 半解析法 螺旋槽 

分 类 号：TH136[机械工程—机械制造及自动化]