环形梯度多胞结构的多工况耐撞性研究  

Research on Annular Gradient Multi-cell Structure Crashworthiness under Multi-impacting Cases

作　　者：张勇[1] 曾意[1] 徐翔[1] 林继铭[1] 赖雄鸣[1] 

机构地区：[1]华侨大学机电及自动化学院,厦门361021

出　　处：《中国机械工程》2018年第4期485-492,498,共9页China Mechanical Engineering

基　　金：国家自然科学基金资助项目(51675190;51305143);福建省自然科学基金资助项目(2015J01204)

摘　　要：针对传统多胞薄壁结构在受到冲击时峰值力过大以及在斜向碰撞时易产生全局弯曲而失稳的问题,提出了一种新颖的具有梯度材料分布特性的环形梯度多胞管。提出并推导了环形多胞结构的平均碰撞力的理论模型,并进一步采用实验方法验证了理论模型的可行性。采用数值分析的方法,对比研究环形梯度多胞结构和均匀多胞结构在多角度冲击工况下的吸能特性。研究结果显示:梯度多胞结构比均匀多胞结构具有更好的能量吸收能力和承载特性,尤其在大角度倾斜冲击工况下,梯度多胞结构具有更明显的耐撞性优势;并且,随着梯度指数的增大,梯度多胞结构的峰值力、能量吸收能力都会降低,并呈现逐渐收敛的趋势,梯度厚度区间也对梯度结构的耐撞性有重要影响。In view of the facts that traditional uniform multi-cell structure existed the defects of high peak forces when they were impacted and instability because of global bending in the oblique collisions,a novel annular gradient multi-cell tube with gradient material distribution was proposed herein.Firstly,theoretical model of the mean crushing forces about annular multi-cell tubes was derived.Then,relevant experiments were carried out to validate the accuracy of theoretical model.Furthermore,numerical simulation method was used to investigate the energy absorption performances of annular gradient multi-cell structures and corresponding uniform multi-cell structures under the multiple impacting conditions.The results show that the gradient multi-cell structures have better energy absorption capacity and load-bearing characteristics than that of the uniform multi-cell structures,especially,the crashworthiness of gradient multi-cell structures presents more obvious advantages under the large angle impact conditions.Besides,the peak forces and the energy absorption capacity of the gradient multi-cell structures gradually reduce and reach convergence with the increase of gradient exponent,meantime,thickness interval of gradient structures also has important influences on crashworthiness of the gradient structures.

关 键 词：环形梯度多胞 耐撞性 斜向冲击 能量吸收 

分 类 号：U271.1[机械工程—车辆工程]