基于梯度密度的非均质蜂窝结构面外压缩性能及优化设计

Out-of-plane compression performance and optimization design of heterogeneous honeycomb structure based on gradient density

提出了一种胞元相对密度呈梯度分布的非均质蜂窝结构,采用参数化设计方法建立了模型,基于试验和有限元分析,研究了梯度系数和胞元尺寸对梯度密度蜂窝结构在面外压缩条件下变形模式和力学响应的影响,并进一步对梯度密度蜂窝结构的吸能特性进行了优化设计。仿真结果表明,在面外准静态压缩条件下,梯度密度非均质蜂窝结构的变形模式与普通蜂窝相似,梯度系数对初始峰值应力的影响较小,具有一定面内正梯度的蜂窝具有更高的平台应力,结构比吸能随着梯度系数的增大而增大。蜂窝初始峰值应力随胞元尺寸的增大而小幅提高,结构比吸能随胞元尺寸的增大先减小后增大。优化结果表明,优化后的梯度密度蜂窝结构峰值冲击力下降了74.3%,比吸能提升了1.6%。

A heterogeneous honeycomb structure whose relative density of cell presents gradient distribution was proposed,the model was established using the parametric design method,based on test and finite element analysis,the effects of gradient coefficient and cell size on the deformation mode and mechanical response of the honeycomb structure with gradient density under out-of-plane compression condition were studied,and the energy absorption characteristics of the honeycomb structure with gradient density were further optimized.The simulation results show that the deformation mode of the heterogeneous honeycomb structure with gradient density is similar to that of the ordinary honeycomb under the condition of out-of-plane quasi-static compression.The gradient coefficient has little effect on the initial peak stress.The honeycomb with a certain in-plane positive gradient has a higher plateau stress,and the specific energy absorption of the structure increases with the increase of gradient coefficient.The initial peak stress of honeycomb increases slightly with the increase of cell size,and the specific energy absorption of the structure first decreases and then increases with the increase of cell size.The optimization results show that the peak impact force of the optimized honeycomb structure with gradient density decreases by 74.3%,and the specific energy absorption increases by 1.6%.