﻿ 六韧带手性蜂窝结构覆盖层的动态压缩行为研究
 舰船科学技术  2017, Vol. 39 Issue (10): 55-60 PDF

A study of the dynamic compression behavior of hexagonal honeycomb layer
JIANG Kun, TAO Meng
School of Mechanical Engineering, Guizhou University, Guiyang 550025, China
Abstract: The energy-absorption layer coating the wet surface of ship is able to enhance the effect of anti-shock to some extent. This paper established the finite element analysis model of this structure by using display dynamic finite element software ABAQUS, studied dynamic compression behavior of six ligament chiral honeycomb structure coating layer based on the hyper elastic material, and analyzed the characteristics of coating layer physical parameters such as deformation characteristics, acceleration, stress and energy absorption of the whole which changed with time in the process of dynamic compression. The results show that under the function of same load and different impact velocity, coating layer gets different macroscopic deformation mode, and with the increase of initial velocity, dynamic compression behavior of the coating layer and the performance of energy absorption become more remarkable.
Key words: hexachiral honeycomb     hyper-elastic coating     crush behavior     energy absorption
0 引　言

1 六韧带手性蜂窝结构的几何特征

 图 1 负泊松比六韧带手性蜂窝结构典型胞元示意图 Fig. 1 Cell diagrammatic sketch of hexachiral honeycomb

 图 2 手性蜂窝结构的计算模型 Fig. 2 Calculating model of hexachiral honeycomb with negative Poission’s ratio
2 有限元计算模型

3 数值计算结果分析与讨论

3.1 不同初速度下覆盖层的变性特征
 图 3 为覆盖层在1 m/s压缩速度下不同时刻的瞬态响应节点应力云图 Fig. 3 The transient response of node stress at the speed of 1 m/s

 图 4 为覆盖层在5 m/s压缩速度下不同时刻的瞬态响应节点应力云图 Fig. 4 The transient response of node stress at the speed of 5 m/s

 图 5 为覆盖层在10 m/s压缩速度下不同时刻的瞬态响应节点应力云图 Fig. 5 The transient response of node stress at the speed of 10 m/s

3.2 不同初速度下单元节点加速度比较分析
 图 6 为覆盖层在1 m/s压缩速度下不同时刻的瞬态响应节点加速度云图 Fig. 6 The transient response of node acceleration under the compression speed of 1 m/s

 图 7 为覆盖层在5 m/s压缩速度下不同时刻的节点加速度变化云图 Fig. 7 The transient response of node acceleration under the compression speed of 5 m/s

 图 8 为覆盖层在10 m/s压缩速度下不同时刻的瞬态响应节点加速度云图 Fig. 8 The transient response of node acceleration under the compression speed of 10 m/s

3.3 不同初速度下结构能量变化比较分析
 图 9 覆盖层在不同压缩速度下不同时刻结构动能随时间变化曲线图 Fig. 9 The kinetic energy-time curves of coatings under different compression speed

 图 10 覆盖层在不同压缩速度下不同时刻结构内能随时间变化曲线图 Fig. 10 The internal energy-time curves of coatings under different compression speed

4 结　语

1）六韧带手性蜂窝结构覆盖层在不同的速度下，表现出不同的宏观变形模式或变形特征。低速压缩过程中，可以将其看成准静态静力分析，结构变形缓慢。速度增加以后，圆环孔壁载荷在很短时间内超过弹性屈曲载荷时，圆环节点立即被压溃，覆盖层结构的应力由冲击端向固定端传递。由于惯性效应的作用，会出现局部软化现象，同时会出现一层一层的向固定端传递此种局部变形模式，最后压缩进入密实化阶段。

2）随着压缩速度的改变，单元节点应力、加速度也同时改变，但是结构的力学性能还是具有相似性，随着时间的推移，节点应力及加速度也会有显著的增加，但结构整体依然保持在一个相对稳定的状态。

3）在相同的冲击载荷作用下，初始速度是影响六韧带手性蜂窝结构覆盖层能量吸收的一个重要因素。研究表明，初始速度越大，结构储存的能量越大。

 [1] PRAWOTO Y. Seeing auxetic materials from the mechanics point of view: A structural review on the negative Poisson’s ratio[J]. Computational Materials Science, 2012, 58 : 140–153. DOI: 10.1016/j.commatsci.2012.02.012 [2] HOU Y, TAI Y H, LIRA C, et al. The bending and failure of sandwich structures with auxetic gradient cellular cores[J]. Applied Science & Manufacturing, 2013, 49 (3): 119–131. [3] GIBSON, LORNA J, ASHBY, M. F. Cellular solids: structure and properties [M]. Cambridge University Press, 1999. [4] ZOU Z, REID S R, TAN P J, et al. Dynamic crushing of honeycombs and features of shock fronts[J]. International Journal of Impact Engineering, 2009, 36 (1): 165–176. DOI: 10.1016/j.ijimpeng.2007.11.008 [5] HOU B, PATTOFATTO S, LI Y L, et al. Impact behavior of honeycombs under combined shear-compression. Part II: Analysis[J]. International Journal of Solids & Structures, 2011, 48 (5): 698–705. [6] RUAN D, LU G, WANG B, et al. In-plane dynamic crushing of honeycombs-a finite element study[J]. International Journal of Impact Engineering, 2003, 28 (2): 161–182. DOI: 10.1016/S0734-743X(02)00056-8 [7] RUAN D, LU G. In-plane static and dynamic properties of aluminum honeycombs[J]. Australian Journal of Mechanical Engineering, 2006, 3 (1). [8] WOJCIECHOWSKI K W. Two-dimensional isotropic system with a negative poisson ratio[J]. Physics Letters A, 1989, 137 (s1-2): 60–64. [9] ALDERSON A, ALDERSON K L, ATTARD D, et al. Elastic constants of 3-, 4- and 6-connected chiral and anti-chiral honeycombs subject to uniaxial in-plane loading[J]. Composites Science & Technology, 2010, 70 (7): 1042–1048. [10] SCARPA F, BLAIN S, LEW T, et al. Elastic buckling of hexagonal chiral cell honeycombs[J]. Composites Part A: Applied Science & Manufacturing, 2007, 38 (2): 280–289. [11] SPADONI A, RUZZENE M. Numerical and experimental analysis of the static compliance of chiral truss-core airfoils[J]. Journal of Mechanics of Materials & Structures, 2007, 2 (5): 965–981. [12] 徐时吟, 黄修长, 华宏星. 六韧带手性结构的能带特性[J]. 上海交通大学学报, 2013, 17 (2): 167–172. XU Shiyin, HUANG Xiuchang, HUA Hongxing. Study on the band structure of hexagonal chiral structures[J]. Journal of Shanghai Jiaotong University, 2013, 17 (2): 167–172. [13] 肖锋. 舰艇抗冲防护覆盖层水下抗爆机理及实验研究[D]. 上海: 上海交通大学, 2013. XIAO Feng. Shock resistance and experimental study of the coatings on warship subjected to underwater explosion[D]. Shanghai: Shanghai Jiao tong University, 2013. [14] 库尔. 水下爆炸[M]. 北京: 国防工业出版社, 1960.