伴随变阻尼作用的干摩擦下的车辆系统非线性动力学分析

Nonlinear Dynamics of Vehicle System with Piecewise Linear Viscous and Dry Friction Damping

对分段线性阻尼和干摩擦共同作用下的车辆悬挂系统进行了非线性动力学分析研究,阐述了判定系统周期运动稳定性的理论方法;利用数值模拟方法分析了具有不同阻尼参数组合的系统对简谐激励的振动响应,并分析了由干摩擦引起的粘-滑振动行为.结果表明:提高摩擦力对抑制响应有利,但车辆系统在低速下运行时会出现复杂的粘-滑振动,轮轨之间产生较大的瞬时刚性冲击;而通过增加轮对与侧架的弹性悬挂可以有效减弱这种瞬时刚性冲击.

The nonlinear dynamics of a vehicle suspension system with piecewise linear viscous and dry friction damping was studied. The theoretical method on the stability analysis of a system in periodic motion was presented. And numerical simulation was performed to investigate the responses of the vehicle suspension system to harmonically excited vibration with respect to different combinations of the damping parameters. The stick-slip vibrations induced by dry friction were analyzed in detail as well. As the results, it was favorable to decreasing the responses amplitude of the system to vibration by increasing the friction force. However, the complicated stick-slip vibration took place at a small velocity, which led to a severe instantaneous stiff impact load between the wheel and rail. It was suggested to decrease such an instantaneous stiff impact load by supplementing elastic suspension between the wheelset and side frame.