悬挂式单轨空、重车线路动力学响应分析

基于多体动力学软件Universal Mechanism建立60自由度的悬挂式单轨车辆系统动力学模型,主要基于乘客舒适度评价指标,探讨空、重车以80 km/h速度通过平竖曲线时动力学响应的异同。结果表明,结构的特殊性使得悬挂式单轨驶过缓圆点和缓直点后车体横向摆动幅度明显,车体横向偏角时变率、未被平衡离心加速度及其时变率结果均会产生一个较大的跃变现象,且重车工况下变化量更大。由于重车惯性更大的缘故,导致振动衰减过程中车体横向低频晃动更剧烈,同一平面线路工况下,重车比空车要多3个振动衰减周期;竖曲线条件下空、重车的振动衰减周期基本一致,但重车的最大垂向加速度更大。因此,鉴于空、重车在平竖曲线处动力特性差异的事实,有必要综合考虑两者用以后期悬挂式单轨列车线路参数的确定。

Analyses on Line Dynamic Response of Unload and Load Vehicles of Suspended Monorail

The dynamic model of suspended monorail system with 60 degrees of freedom is set up by using the multi-body dynamic software Universal Mechanism. Based on the passenger comfort evaluation index, this paper discusses the differences and similarities in the dynamic response of unload and load vehicles passing through the planar and vertical curves at 80 km/h. Simulation results show that the particularities of the structure bring about remarkable lateral swing amplitude of the suspended monorail vehicle as it passes through slow circle point and slow straight point. The lateral angle time-varying rate, the unbalanced centrifugal acceleration and the time-varying rate of the car body all generate a large jump phenomenon, and the change is greater under load vehicle condition. Because of the greater inertia of the load vehicle, the lateral sloshing of the car body becomes more intense. Under the same planar line condition, the load vehicle has three more vibration attenuation periods than the unload vehicle. The vibration attenuation periods of both unload and load vehicles are basically consistent under the vertical curve condition, but the maximum vertical acceleration of the load vehicle is larger. Therefore, in view of the fact that the dynamic characteristics of the unload and load vehicles are different in planar and vertical curves, it is necessary to consider both of them to determine the line parameters of the suspended monorail train.