惯性效应对超高速倾斜端面气膜密封稳动态特性影响

研究了惯性效应和端面倾斜对超高速气膜端面密封稳动态特性的影响. 考虑气体惯性效应，建立了气膜端面密封稳动态特性数值分析模型，采用有限差分法求解稳态和微扰雷诺方程，获得端面膜压分布. 数值分析了惯性效应和端面倾斜度对开启力、气膜刚度和泄漏率等稳态性能参数以及刚度系数和阻尼系数等动态特性系数的影响规律，并以获得较大刚度系数为目标，获得了螺旋槽关键几何参数的优选值范围. 结果表明:在超高速条件下，考虑惯性效应后的干气密封泄漏率显著减小，刚漏比明显增大，而开启力、气膜刚度和动特性系数变化不大；倾斜端面气膜密封相较于平行端面气膜密封具有更佳的低频刚度和高频阻尼. 

The Influence of Inertia Effect on Steady Performance and Dynamic Characteristic of Super High-Speed Tilted Gas Face Seal

The influences of inertia effect and face tilt on steady performance and dynamic characteristics of super high-speed gas face seal were investigated. The steady-state and dynamic numerical analysis model of gas face seal were established with considering gas inertia effect. Steady and perturbation Reynolds equation were solved utilizing finite difference method, and pressure distribution was obtained. The influences of inertia effect and face tilt on steady performance, including opening force, film stiffness and gas leakage, and dynamic characteristics, including stiffness and damping coefficient, of gas face seal were analyzed numerically. Furthermore, the optimal geometrical parameters of spiral groove of gas face seal were obtained for large stiffness coefficient. Results showed that inertia effect would significantly decrease leakage and significantly increase stiffness-leakage ratio at the super high-speed, while the opening force, film stiffness and dynamic characteristic coefficient changed little. There were better dynamic stiffness and damping characteristics at high and low frequencies with considering inertia effect and face tilt.