变载偏斜圆柱滚子轴承打滑动力学分析

Dynamic Skidding Behavior of Skew Cylindrical Roller Bearings under Time-variable Loads

考虑径向间隙、滚子凸度等因素,采用切片方法处理偏斜滚子与滚道之间的三维线接触问题,提出径向力和弯矩联合作用下圆柱滚子轴承载荷分析方法;基于Hertz接触和弹流润滑理论,获得了滚子与内外滚道之间的时变摩擦力和摩擦力矩,进而考虑滚子与保持架之间的非连续弹性碰撞,建立变载偏斜圆柱滚子轴承打滑非线性动力学模型。与文献结果、试验测试结果的对比,验证了所提出的动力学模型的准确性。数值仿真结果表明:增加径向力、增加弯矩、增加时变径向力幅值均会降低滚子的最大打滑速度;时变径向力会改变打滑速度的波动周期。

Considering the radial clearance and roller crown profile, the load distribution analysis of cylindrical roller bearings under combined radial forces and bending moments is conducted by utilizing the slice method to solve the three dimensional line contact problem. The time-variable friction forces and moments between the skew roller and inner/outer raceways are then derived based upon the Hertz contact theory and elastohydrodynamic lubrication. By taking the discontinuous contacts between the roller and cage into account, a nonlinear dynamic model is established for analyzing the skidding behavior of skew cylindrical roller bearings under time-variable loads. Through comparisons with both reference and experimental results, the proposed model is verified. From detailed numerical simulations, it is shown that increasing the values of radial load, bending moment or amplitude of time-variable load would all reduces the maximum roller slipping velocity, and attenuates the roller skidding. After considering the time-variable radial load, the frequency of time-varying slipping velocity is not the orbital speed but the combination of the inner race frequency and orbital speed.