旋转型负泊松比星形蜂窝结构能量吸收特性研究  

Study on Energy Absorption Characteristics of Rotating Star-Shaped Honeycomb Structure with Negative Poisson's Ratio

作　　者：张宝庆[1] 蒋森 Baoqing Zhang;Sen Jiang(Changchun University of Science and Technology,School of Mechanical and Electrical Engineering,Changchun,130022)

机构地区：[1]长春理工大学机电工程学院,长春130022

出　　处：《固体力学学报》2025年第1期129-148,共20页Chinese Journal of Solid Mechanics

摘　　要：负泊松比蜂窝结构具有独特的力学特性以及良好的能量吸收能力,现已被广泛应用于冲击防护领域.在动力冲击作用下,负泊松比蜂窝结构局部动态应力的演化与胞元微结构的改变息息相关.当前对负泊松比结构的研究主要集中在通过设计具有内凹变形机制的胞元以提高整体结构的吸能能力,忽略了对已有模型进行结构优化,对其它旋转变形吸能机制的研究也有欠缺.为了进一步改善负泊松比星形蜂窝结构在承受面内冲击时的动力学响应,本文拟围绕胞元的旋转特性展开研究.在传统星形蜂窝结构的基础上,对其结构进行进一步优化设计,利用耦合思想赋予星形蜂窝胞元自旋转的变形吸能机制.基于相对密度相等原则通过内旋与外旋得到了两种具有双重负泊松比效应的旋转型星形蜂窝胞元:内旋型星形蜂窝胞元和外旋型星形蜂窝胞元.利用数值模拟的方法深入对比研究了不同蜂窝结构在面内冲击载荷下的吸能特性,探究同时具备内凹和旋转两种变形机制的胞元对蜂窝结构吸能特性的影响.基于一维冲击波理论和能量吸收效率方法,给出了星形蜂窝动态平台应力和密实应变的经验公式,建立了计算星形蜂窝结构相对密度的公式.根据临界速度理论,确定了星形蜂窝结构的第一临界速度和第二临界速度.采用显式动力有限元法,研究了旋转型星形蜂窝结构在不同冲击速度下的动态响应,以模型宏微观变形模式、平台应力、比吸能等为评价指标对仿真结果进行了对比分析.结果表明,新型结构在被冲击时胞元都是先发生自身旋转变形然后发生内凹变形,宏观上具有更强的负泊松比效应.在中速20 m/s的冲击下,内旋型蜂窝结构的平台应力更高、平台应力稳定性更好.外旋型蜂窝结构在平台阶段的应力波动较为剧烈,但在高速120 m/s的冲击下具有较高的比吸能.本文的研究结果表明The negative Poisson's ratio honeycomb structure is widely used in the field of impact protection because of its unique mechanical properties and excellent energy absorption capacity.The evolution of local dynamic stress in this structure is closely related to changes in its cellular microstructure under dynamic impact.Current research on negative Poisson's ratio structures mainly focuses on improving overall energy absorption capacity of the structure by designing cells with concave deformation mechanism,often ignoring the structural optimization of existing models and lacking exploration of other energy absorption mechanisms of rotary deformation.To further improve the dynamic response of star-shaped honeycomb structures with negative Poisson's ratio under in-plane impacts,the rotation characteristics of cells are studied in this paper.Building on traditional designs,the star-shaped honeycomb structure is further optimized,and the deformation energy absorption mechanism of star-shaped honeycomb cell is endowed with the coupling idea.Based on the principle of relative density equality,two types of rotating star-shaped cellular cells with double negative Poisson's ratio effect are obtained by internal rotation and external rotation:internal star-shaped cellular cells and external star-shaped cellular cells.The energy absorption characteristics of different honeycomb structures under in-plane impact loads are studied using numerical simulations,and the influences of both concave and rotating deformation mechanisms on the energy absorption characteristics of honeycomb structures are investigated.Based on one-dimensional shock wave theory and energy absorption efficiency method,empirical formulas for dynamic platform stress and dense strain of star-shaped honeycomb structures are given,and the formulas for calculating their relative density are established.According to the theory of critical velocity,the first and second critical velocities of the starshaped honeycomb structure are determined.The dynamic response of

关 键 词：负泊松比 内旋 外旋 旋转型星形蜂窝 

分 类 号：O347.3[理学—固体力学]