T型槽端面密封气膜热弹流润滑动态稳定性

对T型槽端面密封气膜热弹流润滑动态稳定进行了分析. 考虑端面热变形和弹性变形以及辅助密封的阻尼特性，数值分析了不同振动频率下密封气膜动态压力分布和温度分布规律，并利用小扰动方法分析了外界扰动频率对气膜刚度、阻尼和振幅的影响规律. 结果表明:高压和高速条件下，密封端面的弹性变形和热变形产生发散间隙，导致密封气膜厚度显著降低；外界扰动产生附加压力和温度分布，刚度随扰动频率的增加而迅速增加，阻尼随扰动频率的增加而迅速下降；一定扰动频率范围内，轴向振幅与扰动频率成对数线性关系增加，辅助密封阻尼使得密封气膜的振幅显著上升. 

Thermoelastohydrodynamic Gas Lubrication of T-Groove Face Seals: Stability of Sealing Film

Dynamic thermal characteristics of sealing film for T-grooves gas face seals were investigated considering thermal and elastic distortions. Dynamic fields of gas film pressure and temperature were presented at different perturbation frequencies. Then dynamic coefficients of gas film stiffness and damping as well as the amplitude-frequency characteristic was numerically calculated with the perturbation method. Results show that thickness of sealing film decreased significantly due to the elastic and thermal distortions of seal faces at high seal pressure and speed. Ambient perturbation generated additional distributions of pressure and temperature. With the increase of perturbation frequencies, the dynamic coefficient of stiffness increased sharply while the dynamic coefficient of damping decreased. The amplitude perturbation presented a logarithmic increase with increasing perturbation frequency in a range of perturbation frequencies, and the damping induced from the second seal made the amplitude increase sharply.