带弹性支承的角接触球轴承动态特性分析

摘要

针对航空发动机中的轴承支承模型,在有限元分析和轴承动力学的基础上,采用修正的Craig-Bampton 固定界面模态综合法,建立了弹性支承结构与刚性的轴承外圈、轴承座之间的耦合连接,开发了带弹性支承的角接触球轴承动力学分析模型,分析并讨论了不同工况下,弹性支承体对轴承振动特性的影响.结果表明:与刚性支承相比,弹性支承能够降低系统固有频率下的振动幅值.轴承在轴向力作用下,力较小时,增大支承体的刚度能够降低振动幅值,力较大时,采用适当刚度的弹性支承有利于减小振动幅值；轴承在径向力作用下,存在一个合理的弹性支承刚度,使径向振动幅值达到最小.%Taking a bearing support model of aero-engine as the object of study,the mathematical model of dynamic analysis for the angular contact ball bearing with elastic support is established using modified Craig-Bampton component mode synthesis method which coupling the elastic support with the outer ring and housing based on finite element method and bearing dynamics analysis.The factors of elastic support which influence the vibration characteristics of bearing system under different working conditions are analyzed and discussed.The analysis results show that elastic support is able to decrease the amplitude value caused by inherent frequencies compared with rigid support.Under a small axial load,increasing the rigidity of the elastic support is more helpful for decreasing the magnitude of beating vibration;under a heavy load,taking the elastic support with the proper rigidity is benefit for decreasing the magnitude of bearing vibration.There is a reasonable rigidity of elastic support to get the minimum of radial vibration amplitude.