铁道车辆底架前端承载式吸能结构设计及优化

Design and optimization of bearing type energy absorbing structure at the front end of railway vehicle underframe

列车在碰撞过程中,车辆底架前端极易发生变形,而现有底架主要设计为承载结构,不具有吸能能力,因此,承载吸能一体式车辆底架结构对列车被动安全保护起到非常重要的作用。为此,采用拓扑优化方法对某列车头车原型车底架前端正面碰撞下的耐撞性能进行改进。根据拓扑优化结果,提出无填充方管四纵梁设计和泡沫填充方管四纵梁设计的2种耐撞性方案,同时与原始方案进行对比。研究结果表明:由这2种优化方案所得的碰撞力峰值均比原始设计方案所得的峰值低,无填充方管四纵梁设计密实化阶段碰撞力上升至2.73035 MN开始卸载,其碰撞力峰值比原始设计值降低51.51%,泡沫填充方管四纵梁设计的吸能量比方管四纵梁设计的吸能量提升12.19%。

In the process of train collision,the front end of vehicle underframe is prone to deformation,while the existing underframe is mainly designed as a bearing structure without energy absorption capacity,and therefore,the design of rail vehicle underframe as a load-bearing and energy absorption integrated structure plays a very important role in train passive safety protection.The topology optimization method was used to improve the crashworthiness in the front end of the underframe of a prototype vehicle under frontal collision.According to the topology optimization results,two crashworthiness schemes of without filled square tube four longitudinal beam design scheme and foam filled square tube four longitudinal beam design scheme were proposed,and it was compared with the original scheme.The results show that the peak value of collision force of the two optimization schemes is lower than that of the original design,and the collision force of the four longitudinal beam is increased to 2.73035 MN at the beginning of the design of the four girders.The peak collision is 51.51%lower than that of the original design,and the energy consumption of four longitudinal beams of the foam filled square tube is increased by 12.19%than the four longitudinal beam.