双跨弹性转子系统弯扭摆耦合非线性故障特征分析

建立了非对称弹性支承下,带有基础松动-碰摩耦合故障的双跨转子系统弯扭摆耦合非线性动力学模型.应用数值方法研究双跨转子弯扭摆耦合振动下的动力学特性,利用分岔图、幅频特性曲线图、相图及幅值谱图,分析了摆振对于双跨转子系统的影响,揭示了不同结构参数下该类转子系统的典型非线性特征,为该类转子系统故障诊断提供依据.结果表明:摆振对双跨转子系统的运动影响显著;具有松动故障的转子系统非线性幅频特性曲线呈现不光滑的多个波峰

Characteristic Analysis on Nonlinear Faults of Two-Span Rotor System Due to the Combination Vibration of Bending,Torsion and Swinging

With respect to an asymmetrically elastically supported two-span rotor system under the fault coupling loosened pedestal with tub-impact, a nonlinear dynamic model was developed to study numerically the dynamic characteristics of the system during a combination vibration of bending, torsion and swinging. Analyzing the effect of swinging on the system via the bifurcation diagram, phase diagram and amplitude-frequency spectrum, the typical nonlinear characteristics of such rotor systems with different structural parameters were revealed, thus providing a reference to the fault diagnosis of such rotor systems. The results showed that the effect of the vibration due to swinging on a running two-span rotor system is of significance, and that the nonlinear amplitude-frequency characteristic curve of a rotor system with looseness fault presents several unsmoothed peaks.