动能块超高速碰撞多层防护结构的毁伤特性数值模拟

Based on finite element method-smoothed particle hydrodynamics (FEM-SPH) adaptive algorithm of finite element software LS-DYNA, the damage characteristics of a multi-layer protective structure caused by the hypervelocity impact of a kinetic energy block are numerically simulated. Combined with the dimensional analysis method, the effects of the mass and the impact velocity of the kinetic energy block on the perforation characteristics of the multi-layer protective structure are analyzed. The results show that when other parameters remain unchanged and within the range of mass and impact velocity studied in this paper, all kinetic energy blocks can penetrate 17 layers of aluminum alloy plates and form debris clouds behind the target. During the impact process, spallation occurs in the kinetic energy blocks and the aluminum alloy plates. The perforation diameter of the first layer of the aluminum alloy plate increases approximately as a power function with the increase of the mass of the kinetic energy block, and the fitting error is within 5%. The perforation diameter of the second layer of the aluminum alloy plate also increases approximately as another power function with the increase of impact velocity, and the fitting error is less than 10%. The head velocity of the debris cloud increases linearly with the increase of impact velocity. The research results can lay a foundation for analyzing mass and velocity distribution of debris cloud behind target and establishing impact load model.