利用显式动力有限元方法数值讨论了缺陷(胞壁缺失)分布不均匀性对蜂窝材料面内冲击性能的影响。首先,参考理想六边形蜂窝材料在不同冲击速度下的变形特性,将蜂窝材料划分成9个区域,在此基础上讨论了缺陷分布在不同区域时对蜂窝材料面内冲击性能的影响。研究表明,在冲击载荷作用下,除了缺失率以外,蜂窝材料的面内冲击性能也依赖于缺陷的分布,且在中低冲击速度时表现出更高的敏感性。随着缺失率的增加,蜂窝材料的平台应力明显减小,而平台应力对缺失率及冲击速度的敏感性依赖于缺陷的位置。该结论对蜂窝材料的安全性评估及动力学优化设计具有一定的指导意义。
Numerical investigations were conducted by using the explicit dynamic finite element method. In numerical simulations, the honeycomb specimen was divided into nine regions by referring the local deformation modes of a perfect hexagonal honeycomb under different impact velocities. Based on the above treatment, the influences of the defects (cell wall missing) in different regions on the inplane dynamic properties of honeycombs were discussed. The results show that except for the cell wall missing ratio, the dynamic performance of the honeycomb relies on the defect location. Especially under middle or low impact velocities, it displays higher sensitivity. The plateau stress relates to the cell wall missing ratio and the impact velocity, whose sensitivity is determined by the defect location.