椭圆形泡沫填充薄壁管斜向冲击吸能特性仿真研究

摘要

In order to improve the crashworthiness of the vehicles under oblique collision,a novel foam-filled oval tube was proposed. The specific energy absorption (SEA ) and peak crushing force (PCF ) were adopted as crashworthiness indices.Then a finite element simulation was used to analyze the effects of structural parameters, including the oval radial rate,wall thickness and foam density on the energy-absorbing characteristics of the tube.The results show that:with the reduction of radial rate,the PCF increases under small angle impact and SEA increases under large angle impact.Besides,the SEA and PCF are approximately linear with the wall thickness.When the density of foamed aluminum is 0.1 53 g/cm3 ,the composite SEA of the foam filled tube reaches minimum,and the PCF increases with the increase of foam density.It is advantageous to improve the automobile's crashworthiness and safety performance by reasonably designing the parameters of foam-filled oval tubes.%为了提高汽车在斜向碰撞中的防撞性，提出了一种新型的椭圆形泡沫填充管。以比吸能和冲击力峰值作为评价指标，采用有限元仿真的方法分析了椭圆向心率、壁厚和泡沫铝密度等参数对其斜向冲击吸能特性的影响。结果表明：向心率的减小，在小角度冲击时，可降低冲击力峰值，大角度冲击时，能提高比吸能量；比吸能和冲击力峰值与壁厚近似为线性关系；泡沫铝密度为0．153 g／cm3时，泡沫填充管的综合比吸能最小，而冲击力峰值则随着泡沫密度的增大而增大。因此，合理地设计椭圆形泡沫填充管参数有利于提高汽车的防撞性，从而提高乘员安全性能。