地铁列车双锥内嵌隔板矩形管的耐撞性优化

Crashworthiness optimization of a double-tapered rectangular tube with diaphragms for metro train

为设计具有良好耐撞性能的地铁列车吸能结构,将矩形吸能管的一组对称面引入锥度,并在内部嵌入多个隔板。建立该双锥内嵌隔板矩形管和传统矩形管的有限元模型,对两者耐撞性进行对比,通过准静态轴向压缩试验验证有限元分析的准确性。以双锥内嵌隔板矩形管三个部分的厚度为设计变量,进行试验设计并建立代理模型,为最大化比吸能和最小化峰值力,对双锥内嵌隔板矩形管进行多目标优化。结果表明,双锥内嵌隔板矩形管在准静态压缩下呈现稳定而规律的变形,耐撞性能优于传统矩形管;两个优化目标具有一定的互斥性,根据实际工程对各优化目标进行权重分配,能够于帕累托前沿中应用权函数实现最优设计方案的选择。

In order to improve crashworthiness of rectangular energy-absorbing tube for metro trains, taper was introduced into the tube’s one set of symmetric planes and diaphragms were embedded inside the tube. The crashworthiness of this double-tapered rectangular tube with diaphragms(DTRTD) and that of a traditional rectangular tube were compared with their finite element models, the correctness of the corresponding finite element analysis was verified by quasi-static axial compression tests. Thicknesses of three parts of DTRTD were taken design variables, test design was performed and the surrogate model was established. Multi-objective optimization of DTRTD was done to maximize ratio energy-absorption, and minimize force peak values. The results showed that DTRTD reveals stable and regular deformation under quasi-static compression, and its crashworthiness is better than that of the traditional rectangular tube;the two optimization objectives are mutually exclusive, according to the actual project, weight assignment was done for each optimization objective, and weight function can be applied in Pareto frontier to realize the selection of the optimal design scheme.