正方形自填充蜂窝结构异面平台应力的研究

目的 为了促进正方形自填充蜂窝的合理使用，研究其异面平台应力随冲击速度、壁厚边长比和自填充级数的变化规律。方法 利用ANSYS/LS-DYNA建立基于胞元阵列的正方形自填充蜂窝异面冲击分析的有限元模型。对自填充级数为0的正方形蜂窝进行异面压缩试验和相应的仿真分析，证明有限元模型的可靠性。基于简化的超折叠单元理论，建立蜂窝准静态平台应力的理论模型，并证明理论模型的可靠性。结果 正方形自填充蜂窝在大的壁厚边长比和冲击速度下拥有更高的动态平台应力;在自填充级数由0变为1时，动态平台应力增长率最大。结论 在其他因素不变的情况下，正方形自填充蜂窝的异面动态平台应力与冲击速度的平方呈线性关系，与壁厚边长比呈幂指函数关系，其增长率随自填充级数逐级递减。基于数值模拟结果，得到了不同自填充级数下正方形自填充蜂窝异面动态平台应力的经验公式。

Out-of-plane Plateau Stress of Square Self-filled Honeycomb Structure

The work aims to promote the rational use of square self-filled honeycombs by studying the change rules of their out-of-plane plateau stresses with impact velocity, ratio of cell wall thickness to side length and self-filling order. ANSYS/LS-DYNA was used to establish the finite element model based on cells array for the out-of-plane impact analysis of square self-filled honeycombs. The out-of-plane compression test and corresponding simulation analysis were carried out on the square honeycomb with self-filling order of 0 to prove the reliability of the finite element model. Based on the simplified super folded element theory, the theoretical quasi-static plateau stress model of square self-filled honeycomb was established and verified by the simulation results. The square self-filled honeycomb higher dynamic plateau stress with increasing ratio of cell wall thickness to side length and impact velocity. When the self-filling order changed from 0 to 1, the growth rate of the dynamic plateau stress was the largest. When other factors are fixed, the out-of-plane dynamic plateau stress of square self-filled honeycomb has a linear relation with the square of velocity and a power function relation with the ratio of cell wall thickness to side length, and the growth rate decreases gradually with increasing self-filling order. Based on the finite element simulation, the empirical formulas of dynamic plateau stress are obtained for the square self-filled honeycomb with different self-filling orders.