摘 要

随着我国经济的高速发展，汽车产业日见壮大，我国汽车保有量也在成倍递增，汽车碰撞等交通事故频繁发生，设计出具有优良性能的吸能盒对汽车的碰撞安全性有着至关重要的作用。现如今各种以仿生学为研究基础的研究所和研究院等科研机构在全世界范围内的各大学科研院陆续成立和发展起来，为改善汽车吸能结构的吸能效率，本文以甲虫鞘翅与蜘蛛网为生物原型，开展设计新颖的仿生薄壁吸能结构。采用计算机仿真对比分析的方法，对所设计薄壁结构耐撞性进行分析，主要围绕三个方面展开：

（1）以甲虫的鞘翅微观结构为生物原型设计的新颖的正多边形仿生微圆薄壁吸能结构具有优良的吸能特性，且不同正多边形的截面布置对结构的耐撞性有着重要的影响，研究表明，正四边形截面布置薄壁吸能结构与正六边形、正八边形截面布置相比，有着更加优良的碰撞能量吸收能力和碰撞过程的结构稳定性。

（2）以仿蜘蛛网层级结构所设计出新颖的不同层级数的薄壁吸能结构，层级结构也体现出非常优秀的耐撞性能，并且不同的层级阶数的影响也在薄壁吸能结构的耐撞性中占有重要部分，随着层级阶数的增加，仿生薄壁吸能结构的吸收能量性能越好；再以二层级仿生薄壁吸能结构为例，发现不同层级边长相似比对薄壁吸能盒耐撞性能的提高具有潜在优势，并且较小的不同层级边长相似比也有着更好的碰撞吸能特性和碰撞过程维持结构稳定性的能力。

（3）综合仿甲虫鞘翅与仿蜘蛛网吸能结构的优点，结合甲虫鞘翅微圆结构与蜘蛛网层级结构设计出新颖的仿生层级微圆薄壁吸能结构，发现不同层级微圆直径相似比对薄壁吸能结构的耐撞性有所影响，通过对比分析，较大的不同层级微圆直径比可以提高薄壁吸能盒碰撞吸能特性，并且较大的不同层级微圆直径比薄壁吸能结构碰撞过程也有着更好的结构稳定性。

关键词：层级微圆结构、耐撞性、吸能、仿生学、有限元

Abstract

With the rapid development of China's economy, the automobile industry is growing day by day, and the number of automobiles in China is also increasing exponentially. Traffic accidents such as automobile collisions occur frequently. The design of energy absorption boxes with excellent performance is of vital importance to the safety of automobile collisions. Nowadays, various research institutes and institutes based on bionics have been established and developed in universities and research institutes all over the world. In order to improve the energy absorption efficiency of automobile energy absorption structure, this paper takes beetle elytral wing and spider web as biological prototypes to design novel bionic thin-walled energy absorption structure. The crashworthiness of the designed thin-wall structure is analyzed by computer simulation and comparative analysis, which is mainly carried out in three aspects:

(1) To the beetle namib microstructure for the regular polygon bionic biological prototype design of novel micro circular thin-walled energy-absorbing structure, with excellent properties and different arrangement of regular polygon cross section to have great effect on the crashworthiness of the structure, studies have shown that decorate square cross-section thin-walled energy-absorbing structure compared with hexagonal, are octagon section layout, has more excellent impact energy absorption capacity and structure stability of the collision process.

(2) To imitate the spider web hierarchy design a novel on the number of different levels of thin-walled energy-absorbing structure, the hierarchy structure also reflects the very good resistance performance, and the influence of different level order also in the crashworthiness of thin-walled energy-absorbing structure occupies an important part, with the increase of hierarchy order, bionic thin-walled energy-absorbing structure energy absorption performance, the better; Taking the bionic two-level thin-wall energy-absorbing structure as an example, it is found that the similar ratio of side lengths at different levels has potential advantages in improving the crash-resistance performance of the thin-wall energy-absorbing box, and the smaller similar ratio of side lengths at different levels also has better energy-absorbing characteristics of collisions and the ability to maintain structural stability in the collision process.

(3) Integrated with imitation imitation beetle namib cobweb energy-absorbing structure, the advantages of combining beetle namib micro circular structure and the spider web hierarchy design a novel bionic level micro round thin-walled energy-absorbing structure, the small diameter at different levels found similar than the crashworthiness of thin-walled energy-absorbing structure influence, through the comparative analysis of different levels of the small diameter ratio could increase can thin wall box crash energy absorption characteristics, slightly rounded at different levels and the larger diameter than the thin-walled energy-absorbing structure collision process also has a better structure stability.

Key words: hierarchical microcircular structure; crashedness; energy absorption; bionics; finite element

目 录

第1章 绪论 1

1.1仿生学概述 1

1.1.1仿生学的定义与发展 1

1.1.2仿生学的研究方法及内容 2

1.1.3仿生学的前景和意义 3

1.2研究的背景及意义 3

1.3国内外研究现状 5

1.4 本文的主要研究内容 7

1.5本文的主要创新点 7

第2章 耐撞性研究的理论基础 9

2.1汽车吸能结构的耐撞性研究方法 9

2.2有限元基本理论 10

2.2.1有限元理论求解法 10

2.2.2接触-碰撞的基本算法 11

2.2.3 时间步长和沙漏控制 12

2.3 Hypermesh软件介绍 13

2.4吸能耐撞性结构的评价指标 14

第3章 不同类型正多边形耐撞性分析 16

3.1仿生微圆结构的几何模型 16

3.1.1甲虫鞘翅微观结构 16

3.1.2 仿生微圆结构的几何模型 17

3.2仿生微圆结构的有限元模型及分析 18

3.2.1四边微圆结构的有限元模型 18

3.2.2有限元模型的分析 18

3.3不同正多边形薄壁管耐撞性分析 19

3.3.1不同截面布置有限元模型 19

3.3.2不同截面布置耐撞性对比 21

3.4本章小结 22

第4章 不同层级边长相似比对结构耐撞性的影响 23

4.1蜘蛛网层级结构 23

4.2仿生层级结构的耐撞性分析 24

4.2.1仿生层级结构的有限元模型 24

4.2.2有限元模型的分析 24

4.3不同层级边长的耐撞性分析 26

4.4本章小结 28

第5章 不同层级微圆直径比对结构耐撞性的影响 29

5.1仿生层级微圆结构 29

5.2仿生层级微圆结构有限元模型 30

5.3有限元模型的分析 30

5.4本章小结 32

第6章 总结与展望 33

6.1总结 33

6.2展望 33

参考文献 35

致谢 37

第1章 绪论

1.1仿生学概述

1.1.1仿生学的定义与发展