含挤压油膜阻尼器的甘蔗切割器转子系统的动力特性

Dynamic Characteristics of the Sugarcane Harvester Cutter's Rotor System with Squeeze Film Damper

为了获得挤压油膜阻尼器对甘蔗收获机切割器立式转子系统的动力学特性的影响,本文将含该阻尼器的切割器系统简化成刀盘-SFD立式转子系统,建立了其非线性动力学模型.基于该模型,运用数值求解方法并利用不同工作转速时刀盘的轴心轨迹、Poincare映射、FFT频谱特性对含\不含挤压油膜阻尼器的切割器轴心轨迹进行对比分析,结果表明,当Ω=500 r·min-1和Ω=800 r·min-1时,含SFD与不含SFD切割器系统的轴心轨迹分别呈4倍周期和3倍周期分岔,SFD能降低刀盘轴心振动幅值,最大幅值减小到原来的1/3,且工作转速越高,挤压油膜阻尼器的减振效果越明显.

In order to obtain the effect data on the squeeze film damper （SFD） on the dynamic characteristics of sugarcane harvester cutter system, in the report, the cutter was simplified to a vertical cutter-SFD rotor system, and the nonlinear dynamic equations were founded. Based on the model, the numerical solution method was per- formed, and the axis track curve, Poincare mapping, and amplitude-frequency feature were used to compare the axis path of the vertical cutter-SFD rotor system with that of the rotor system without SFD. The results indicated that, when/2 = 500 r ~ min - 1 and/＇2 = 800 r ~ rain - 1, the orbit of rotor center of the cutter system that with SFD and excluding SFD show 4 and 3 period-doubling bifurcation, respectively, SFD could damper the vibration of cutter effectively, the amplitude was reduced to 1/3 of the original, and the higher working speed, the more ob- vious the oil film damper dampinz effects.