非线性数值模拟柱面气膜密封动态特性

针对气膜密封研究中密封气膜动态特性分析难点问题，采用非线性数值模拟法对柱面气膜密封系统的动态特性进行研究[D].建立了柱面气膜密封系统的动力学模型，给出了基于有限元数值方法的瞬态气体雷诺方程（含时间项）与系统动力学方程的耦合求解流程和方法，数值仿真给出了柱面密封环的中心轨迹图、确定了一定转速下的临界无量纲质量、不同密封环无量纲质量时等量位移扰动下系统的响应图，分析了密封环无量纲质量对系统稳定性的影响.结果表明:光滑柱面气膜密封系统存在临界无量纲质量，临界时系统受扰后处于半频涡动状态，随着密封环无量纲质量的增加，受扰后系统收敛时间变长，稳定性变差. 

Nonlinear numerical simulation for dynamic characteristic of gas cylinder film seal

Aiming at solving the dynamic characteristic as a problem in the research and design of gas film seal,the seal dynamic behavior of gas cylinder film seal was studied theoretically by employing the nonlinear numerical simulation method.The dynamics analysis model of gas cylinder film seal system was established to solve the coupling with the Reynolds equation (including time terms).Through finite element numerical simulation,the trajectory diagram of the sealing ring,the critical dimensionless mass of the seal system and the response to a displacement impact were obtained.The influence of the sealing ring dimensionless mass on dynamic stability was studied.The results show that the critical dimensionless mass of the smooth gas cylinder film seal could be found,and the whirl at the stability threshold is under "half-frequency" state.With the increase of the sealing ring dimensionless mass,the time of returning to a stable state becomes longer and the stability becomes worse.