柔性联轴器平行不对中轴系振动特性分析

Vibration Characteristics Analysis of Rotor System with Flexible Coupling Parallel Misalignment

考虑联轴器弯曲、扭转和横向柔度的影响,分析了转子轴承系统在联轴器平行不对中情况下的振动特性。计及转子的径向位移、偏转角和扭转角自由度,并考虑轴承特性的各向异性,利用各自由度之间的耦合关系,通过第二类拉格朗日方程建立了平行不对中多转子系统的动力学控制方程。通过数值方法求解非线性方程,得到了稳定运行时转子振动的时域波形、频谱及轴心轨迹。平行不对中程度对振动的影响分析表明,在实际可能发生的平行不对中量级下,即不对中量与转子长度之比小于10^(-3)时,横向振动始终以基频分量为主,扭转振动有明显的二倍频分量,未表现出明显的非线性特性。

The dynamics characteristics of rotor system with parallel misalignment are investigated when flexible of coupling is also considered. Radial displacement, bending and torsion of rotor are included in the model, and bearing are assumed anisotropic.Firstly, dynamic governing equations of rotor system with parallel misalignment are established with the Lagrange equation. Then,Runge-Kutta numerical integration method is used to solve the nonlinear governing equations;and responses in time and frequency domain and orbit of rotor system with different parameters are obtained and discussed. Finally, the effect of the magnitude of parallel misalignment on vibration responses is analyzed, when the ratio of the misalignment to the rotor length is less than 10^(-3),some results are obtained as follows: the transverse vibration is always dominated by the fundamental frequency component;the torsional vibration has considerable amount of double frequency components;furthermore, the coupling of lateral and torsional vibrations is very weak and does not show obvious nonlinear characteristics.