航空发动机齿轮泵轴承润滑及抗偏载特性分析

Study on the Lubrication and Anti-eccentric Load Characteristics of theAero Gear Pump Bearing

针对航空发动机齿轮泵滑动轴承复杂工况下存在的润滑性能不清晰、摩擦特性不明朗的问题,将转轴转速升高,分析光滑油膜和带槽油膜压力变化,增大入口供油压力,观察承载力变化,同时,施加并增大轴承偏载。结果表明,转速升高,光滑油膜正压增大、负压减小,带槽油膜的负压降低,承载能力显著增长,入口压力对承载力的影响逐渐减弱。存在临界入口压力,使得处在低于该值的工况,转速越高,无量纲摩擦因数越大。偏载持续增大,极大可能导致轴承油膜破裂、润滑失效。存在偏载临界点,使得处于临界点以下的轴承性能较好,高于该点的轴承性能较差。此外,偏载具有刚度增强和阻尼增强的作用。研究结果为齿轮泵滑动轴承设计研发及其国产化提供理论依据。

For the problems of uncertain lubrication performances and tribological characteristics in aero gear pump journal bearing under harsh working condition,the rotational speed is increased to analyze the pressure variation of smooth oil film and the oil film with groove,the oil supply pressure is enhanced to explored the load-carrying capacity and synchronously,the eccentric load is applied and increased.It is shown that with the increase in speed,the positive pressure of smooth oil film increases and its negative pressure decreases,the pressure of the oil film with groove descends and the load-carrying capacity significantly increases.Accordingly,the effect of inlet pressure on the load-carrying capacity is weakened.There is a critical inlet pressure value,so that the higher the speed is,the larger the dimensionless coefficient of friction is when the working condition is below this value.The eccentric load continues to increase,which may lead to the rupture in oil film and lubrication failure.The existence of eccentric load critical point makes the bearing below the critical point has better performance,while the bearing above the critical point has poor performance.In addition,the eccentric load can increase the effect of stiffness and damping.The research results lay a firm theoretical fundamental for the design,development and localization of aero gear pump journal bearing.