带内环槽的螺旋槽干式气体端面密封的静压性能

Static Analysis of a Spiral-Groove Dry Gas Seal with an Inner Annular Groove

针对现场使用的带内环槽的螺旋槽干式气体端面密封,建立了用于预测其端面气膜压力的等温可压缩流二维雷诺方程,在只考虑静压效应的条件下应用有限元法计算了端面开启力、泄漏率、气膜刚度和刚漏比等密封性能参数,并与典型螺旋槽干式气体端面密封(S-DGS)进行了比较.结果表明:与S-DGS相比,前者具有更好的稳定性、润滑性能和开启特性.以获得最大刚漏比为优化原则,综合考虑密封的稳定性、密封性和开启特性,获得了带内环槽S-DGS在静压作用下的端面规则微槽几何参数的优选值,研究结果对有关密封的设计与选用具有指导意义.

A two-dimensional Reynolds equation was established for pressure prediction of the isothermal compressible gas film between the two faces of a spiral groove dry gas face seal with an inner annular groove. The sealing performance, such as opening force, leakage rate, axial film stiffness and the ratio of film stiffness to leakage were calculated by finite element method only considering hydrostatic effect of gas film, and comparison with typical spiral groove gas face seal （S-DGS） were made. The former method run better in term of stability, lubrication and runup. Based on the optimization principle of maximum ratio of film stiffness to leakage, an optimized geometric designs for regular micro-grooves were obtained by static analysis considering sealing stability, sealing ability and runup comprehensively.