滚动轴承-偏置转子系统涡摆耦合动力学特性研究

Dynamic characteristics of a ball bearing-offset disk rotor system with whirling-swing coupling

建立了滚动轴承-偏置转子系统涡摆耦合动力学模型,模型中考虑了转子偏置量及圆盘摆振,滚动轴承模型中考虑了轴承游隙、非线性赫兹接触力及变刚度VC(Varying Compliance)振动等因素。采用数值方法对不同偏置量下,有无考虑圆盘摆振时系统动力学响应进行了计算与比较;分析了轴承游隙变化对不同偏置量的转子动力学性能的影响。结果表明:考虑圆盘摆振时偏置转子的非线性动力响应特征明显增强;相同转速下,不同偏置量的转子系统中频率成分亦不相同;转子偏置程度越大,系统临界转速对轴承游隙变化的敏感度越高。

Dynamic model of a ball bearing-offset disk rotor system with whirling-swing coupled vibration was built considering rotor disk offsetes and disk swing vibration.In the model of ball bearings,clearance of bearings,nonlinear Hertzian contact force between balls and races and varying compliance vibration were considered.Numerical methods were adopted to solve and compare the dynamic responses of the system under different disk offsetes with or without disk swing vibration considered.Effects of bearing clearance variation on the dynamic performance of the model under different rotor disk offsetes were analyzed.It was shown that the nonlinear dynamic response features of the offset disk rotor system are enhanced obviously considering rotor disk swing vibration; the system under different rotor disk offsetes contains diverse frequency components at the same speed; the larger the level of rotor disk offset,the higher the sensitivity of the critical speeds of the system to bearing clearance variation.