建立了交错排布和规则排布的三角形网格圆柱结构有限元模型,分析了这两种三角形网格圆柱结构在不同工况下的动态变形模式、承载能力及能量吸收特性.研究发现:网格结构的变形均随着冲击速度的增加而向冲击端集中,胞元壁厚对变形模式的影响较小;由于变形模式的不同,交错排布的网格结构的承载能力和刚度比规则排布的大;当冲击速度较低时,交错排布和规则排布的网格圆柱结构的吸能能力相差不大,随着冲击速度的提高或胞元壁厚的增加,两种网格结构的吸能能力和吸能效率明显增强,且交错排布的网格圆柱结构表现出更强的能量吸收能力;网格结构吸收的能量绝大部分转化为变形所需的内能,而动能所占比重较小.
In order to investigate the dynamical deformation modes,load-bearing capability and energy absorption behavior under different conditions,the finite element models of grid cylindrical structures filled with stagger-arranged and regular-arranged triangular cells were established.The results indicate that the deformations of both grid structures with different arrangements are gradually concentrated to the impacted end with increasing the impact velocity,while cell wall thickness has little effect on deformation modes.The bearing capacity and stiffness of the staggered arrangement is larger than the regular arrangement because of the different deformation modes.At the lower impact velocity,the energy absorption capacities of the grid structures with different arrangements are approximately the same.With the impact velocity or the cell wall thickness increasing,both of the grid structures have stronger energy absorption capabilities and efficiencies,and the grid structure with stagger-arranged cells has better energy absorption capability than one with regular-arranged cells.Most of the energy absorbed by grid structure is converted into internal energy,while kinetic energy has a less proportion.