形内自相似六边形蜂窝结构的正面冲击吸能特性

Energy-absorbing Performance under Frontal Impact of In-form Self-similar Hexagonal Honeycomb Structures

为了获取理想的吸能缓冲材料,提出了一种形内自相似六边形蜂窝结构,参照典型汽车前保险杠的外形尺寸和正面碰撞工况建立冲击模型,模拟和分析了低、中、高速下形内自相似六边形蜂窝结构正面冲击动态压缩过程、变形模式和特点,研究了分形维数对吸能特性的影响。与圆形、方形结构正面撞击下的各项吸能指标对比发现,在同等条件下,形内自相似六边形蜂窝结构的总吸能、比吸能、吸能效率均优于圆形、方形结构。

This paper proposes an in-shape self-similar hexagonal honeycomb structure in order to gain an optimal buffering and energy-absorbing material.With reference to the external dimensions of a typical automobile front bumper and the frontal collision conditions,the impact model is established to simulate and analyze the dynamic compression process,deformation pattern and characteristics of the frontal impact of the in-form self-similar hexagonal honeycomb structure respectively at low,medium and high speeds,and to study the influence of the fractal dimension on the energy-absorbing characteristics.The comparison of the energy-absorption indexes with those of circular and square structures under frontal impact reveals that,under the same conditions,the total energy absorption,energy absorption rate,and energy absorption efficiency of the in-shape self-similar hexagonal honeycomb structure are all superior to those of the circular and square structures.