摘要
针对浮环轴承双层间隙的结构特点,建立了其润滑模型.在考虑供油压力和油膜破裂的情况下,通过求解基于长轴承理论的雷诺方程,得到了内外油膜周向压力分布情况,并推导了油膜力的解析表达式.在给定浮环轴承结构参数的情况下,利用Matlab软件对润滑模型进行了计算和仿真.分析了诸如载荷、供油压力、转子转速等参数对浮环轴承静平衡位置、油膜连续性以及轴承内间隙润滑的影响.得出了较大的外载荷会导致较大的外油膜偏心率和外油膜空穴区扩大,而供油压力主要影响外油膜的偏位角的结论,并指出载荷的加大会使进入内间隙润滑油量在很宽的转速范围内减小,有可能会导致内膜贫油情况的发生,而增大润滑油注油压力会有效缓解这一现象的发生.
The lubrication model is developed for the floating ring bearing,according to its structural characteristics of double oil films.The circumferential pressure distribution of both outer and inner oil films are obtained through the solution of Reynolds Equation for the infinitely long bearing,which takes into account the lubricant feed pressure and oil film rupture.The analytical expression of the hydrodynamic force is derived.Under the given structural parameters of floating ring bearing,the lubrication model is computed and simulated using Matlab software.The effects of such parameters as load,lubricant feed pressure on the equilibrium position,oil film continuity and inner film lubrication are analysed.It is concluded that a heavy external load can lead to a large eccentricity in the outer oil film and a large cavitation area in the outer oil film,and that the lubricant feed pressure mainly affects the attitude angle of the outer oil film.It also shows that a high load could decrease the lubricant flow rate into the inner oil film within a wide speed range and even lead to the starved lubrication in the inner oil film,which can be effectively improved by increasing lubricant feed pressure.
引文
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