重复冲击载荷下泡沫铝夹芯壳的动态响应  

Dynamic Responses of Aluminum Foam Sandwich Shells under Repeated Impact Loadings

作　　者：朱浩霖 张天辉 刘志芳 ZHU Haolin;ZHANG Tianhui;LIU Zhifang(Institute of Applied Mechanics,College of Mechanical and Vehicle Engineering,Taiyuan University of Technology,Taiyuan 030024,Shanxi,China)

机构地区：[1]太原理工大学机械与运载工程学院应用力学研究所,山西太原030024

出　　处：《高压物理学报》2024年第5期225-237,共13页Chinese Journal of High Pressure Physics

基　　金：国家自然科学基金(12272254);山西省自然科学基金(202203021211170)。

摘　　要：通过数值模拟研究了泡沫铝夹芯壳在重复冲击载荷作用下的变形和能量耗散机理,分析了曲率半径、前后面板厚度分配、芯层厚度和冲击能量梯度对结构抗重复冲击性能和能量吸收能力的影响规律。结果表明:在重复冲击载荷作用下,泡沫铝夹芯壳结构的变形不断累积,前面板局部弯曲变形,芯层局部压缩,后面板整体弯曲变形。随着冲击次数的增加,冲击力峰值逐渐增大,冲击持续时间缩短,结构能量吸收能力降低,整体抗弯刚度增大。每次冲击能量相同时,泡沫铝夹芯壳结构曲率越大,能量吸收能力越强,同时前、后面板5次重复冲击后的中点挠度大于曲率较小的夹芯壳结构。5次重复冲击载荷作用下,前面板厚度较大且后面板厚度较小时,结构的比吸能较低,但后面板中点挠度较小。泡沫铝芯层厚度越大,结构的后面板挠度越小,但总比吸能降低。3种不同梯度的冲击能量作用下,递增能量工况下结构的吸能最多,前、后面板的挠度较大,递减能量工况下结构的吸能最少,前、后面板的挠度较小。The deformation and energy dissipation mechanism of the aluminum foam sandwich shell under repeated impact loads were investigated by numerical simulation.The effects of radius of curvature,thicknesses distribution of the front/back face sheets,core thickness and impact energy gradient on the repeated impact resistance and energy absorption capacity of the structure were analyzed.It is shown that the deformation of the aluminum foam sandwich shell structure accumulates under repeated impact loads,with local bending deformation of the front face sheet,local compression of the foam core,and global bending deformation of the back face sheet.As impact times increases,the peak impact force and integrated bending stiffness increase,and the impact duration and energy absorption capacity decrease.When each impact energy is the same,for aluminum foam sandwich shell structure,the larger the curvature,the higher the energy absorption capacity,while the midpoint deflections of the front and back face sheets after five repeated impacts are larger than that of the shell structure with smaller curvature.Under five repeated impact loads,when the thickness of the front face is large and the back face is small,the specific energy absorption of the structure is lower,but the midpoint deflection of the back face is smaller.The larger the thickness of the aluminum foam core,the smaller the deflection of the back face of the structure,but the total specific energy absorption is reduced.Under the impact energy with three different gradients,the energy absorption of the structure is the highest when the impact energy is increased successively,and the deflections of the front and back faces are larger,while the energy absorption of the structure is the lowest,and the deflection of the front and back faces is smaller when the impact energy is decreased successively.

关 键 词：泡沫铝夹芯壳 重复冲击 动态响应 能量吸收 

分 类 号：O347.3[理学—固体力学] O521.9[理学—力学]