构架结构振动与动态应力仿真研究

SIMULATION OF RAILWAY BOGIE DYNAMIC STRESS AND ELASTIC VIBRATION

首先利用有限单元法,建立了详细的构架有限元模型并求解其各阶振动模态,在此基础上建立了完整的刚一弹性体车辆系统动力学模型;通过动力学模拟计算得到了构架在车辆曲线通过和随机激扰下的结构振动响应;最后,将构架的动力学计算结果返回到有限元中,得到了构架的动态应力时间历程与分布特性。该种研究方式不仅完成了多体系统动力学研究中刚体与弹性体的有机结合,而且为转向架在结构设计阶段通过模拟计算就可获得车辆运行过程中构架的动态应力分布,为评估其疲劳寿命奠定了基础。该仿真技术同样实用于其他相关研究领域,如航空航天、工程机械和公路车辆等。

Firstly, the FEM model of the bogie of the car is established and the modes are calculated in the FEM software. Secondly, the multi-body vehicle dynamic system model is set up in which the carbody, axleboxes and the wheelsets are taken as rigid body and the bogie of the truck is regarded as elastic one. With time integration, the structural vibration of the railway bogie and dynamic responses of the other parts of the car are achieved while the vehicle negotiates a curve and runs on straight track with the stochastic excitation. Finally, the dynamic stress distribution characteristics of the bogies in time domain are obtained after the dynamic responses of the bogies are input to the FEM. In this process, not only the more accu- rate dynamic responses of the bogies can be acquired, but also the dynamic stress distribution and the structural vibration of the railway bogie can be achieved. For one thing, this research technology combines the elastic body with the rigid one as a tightly system. For another, it is very useful to obtain the dynamic stress and evaluate the service life of bogie in its structural design stage. This simulation technology can also be fully used in other mechanical research fields such as road vehicles, military tanks and aeronautic machines.