摘要
考虑转子交角不对中和质量不平衡等因素,研究了在滑动轴承支承下柔性转子-轴承耦合系统的非线性动力学行为。首先,基于转子间交角不对中的约束关系,利用第二类Lagrange方程推导了具有交角不对中故障的柔性多转子系统运动微分方程。采用数值方法,分析系统的非线性振动特性,例如,系统的轴心轨迹、响应频谱和最大Lyapunov指数等。结果表明:在较低转速时,系统主要呈现出与转速同步的周期运动特性。随着转速的提高,稳态响应在某些参数下出现分叉、跳跃以及混沌等非线性现象。最后讨论了交角不对中量以及质量不平衡对系统动力学特性的影响。
The non-linear dynamical behaviors caused by the faults of angular misalignment and mass unbalance of the journal bearing supported flexible rotor-bearing system are investigated in this paper.Firstly,the motion equation of the rotor system is derived by the second class Lagrange method with the effects of the motion relation between the two rotors,in which a rheonomic holonomic constraint characterized by the angular misalignment is embedded.Then its nonlinear vibration features,such as the frequency spectra,rotor orbit and Poincarésection,and the largest Lyapunov exponent under different conditions are primarily analyzed based on numerical techniques.The results reveal that the vibration of the rotor system are synchronous at low speed,while as the rotating speed increase,some non-linear characteristics such as jumping,period-doubling and chaotic motions will occur.Furthermore,the parameter analysis for the effects of angular misalignment and mass unbalance is also discussed.
引文
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