仿龟甲层级吸能结构动态响应数值模拟OA

To improve the protective performance of sports helmets against low-velocity concentrated impact loads,a bionic-turtle-shell hierarchical sandwich structure(BHSS)was designed in this paper.Numerical simula-tions were adopted to explore the dynamic response law of BHSS under impact loads,and the effects of carbon fiber lay-up angles,rubber buffer layer thickness,TPMS cell configurations and wall thickness on the punch acceleration response and structural energy absorption characteristics were systematically analyzed.The results show that under the action of 73.98 J impact energy,the dynamic process of punch penetrating BHSS can be divided into five stages:elas-tic deformation,damage initiation,damage aggravation,stiffness strengthening and rebound.The TPMS porous core layer is the core energy-absorbing component of BHSS,with an energy absorption ratio of 63.76%and an overall en-ergy absorption peak value of 63.77 J for the structure.The carbon fiber lay-up angles of cross-ply,angle-ply and quasi-isotropic ply have a weak effect on the energy absorption peak value of BHSS.The rubber buffer layer can ef-fectively reduce the peak impact acceleration,but with an obvious marginal effect.The BHSS with P-type cell config-uration exhibits the optimal comprehensive buffering and energy-absorbing effect,while increasing the cell wall thick-ness will lead to a significant rise in the peak punch acceleration.