【摘要】 对非线性能量阱(nonlinear energy sink, NES)在汽车传动系统扭振抑制中的应用进行了研究。根据传动系统的结构和振动特点，建立了简化的3自由度传动系统-NES耦合动力学模型；基于增量谐波平衡法联合增量弧长法，推导并求解了耦合系统的频率响应，利用Floquet理论对周期解的稳定性进行判断；在频域和时域上对系统的非线性动力学响应及其影响因素进行了分析，并基于能量谱研究了NES的减振性能；最后，基于扩展的5自由度非线性模型对NES进行了参数优化和验证。结果表明，NES的减振性能受其自身刚度、阻尼及发动机激励幅值影响，合理设计NES参数可以高效抑制汽车传动系统的扭转共振，而不恰当的NES参数会促使系统发生高分支周期响应，导致异常振动峰值出现，经优化后的NES可以仅5%的惯量比使传动系统转速波动均方根值降低41.3%,减振效果显著。该研究可为NES在传动系统扭振抑制中的应用及其参数设计提供参考。更多还原

【Abstract】 The application of the nonlinear energy sink(NES) in suppressing the torsional vibration of an automotive powertrain system was studied. A simplified 3DOF powertrain-NES model was established according to the structural and vibrational characteristics of the powertrain. Based on the incremental harmonic balance method combined with incremental arc-length method, the frequency response of the coupling system was derived, and the stability of the periodic solution was estimated by the Floquet theory. The nonlinear dynamic response of the system was analyzed in both time and frequency domains, and parametric analyses were also carried out. The vibration suppression ability of the NES was investigated based on energy spectrums, and the NES parameters were finally optimized and validated by virtue of a 5DOF nonlinear model. The results indicate that the damping effect of the NES is influenced by its stiffness, damping and the engine exciting torque. A properly designed NES can effectively attenuate the powertrain torsional vibration, but inappropriate parameters of the NES can lead to the high-amplitude periodic response and yield abnormal vibration peaks. The optimized NES can attenuate the RMS value of powertrain speed fluctuation by 41.3% with only 5% inertia ratio. This study provides references for the application and parameter design of the NES in the torsional vibration suppression of powertrain systems.更多还原