| With the increase of warhead penetration speed and penetration depth,the internal charge will withstand extreme environments with high overload and high strain rates.Based on the artillery-launched warhead,the dynamic response of the charged projectile under high-g impact from different aspects is studied with the numerical simulation method in this paper.The main research contents are as follows:The mode analysis of the charge projectile is carried out to obtain its natural frequencies and modal shape.The Forrestal penetration formula is used to verify the penetration of the projectile by numerical simulation.The results show that there is a axial vibration mode of the charge projectile at a specific external excitation frequency and the corresponding frequency should be avoided during the test;the model method and material model is verified by the Forrestal penetration formula.Numerical simulation method is used to study the process of two kinds of explosive structures falling into concrete ground at different heights.The overload situation of the projectiles and the stress distribution of the charges are analyzed,and the crater status of the concrete ground is experimentally verified.The results show that the impact overload of the projectiles with different charge structures is basically the same;the charge constantly oscillates,the head of the charge is compressed,the tail is pulled,and the middle part will be repeatedly pulled and compressed during the drop impact;in addition,the pit conditions are basically consistent with the numerical simulation results,which proves the rationality of the numerical simulation.Numerical simulation methods are used to study the penetration of the charge projectile into a four-layer concrete targets,focusing on the analysis of the changes of the internal charge of the projectile and the interaction between the charge and the projectile.The results show that when the charge projectile penetrates into the multi-layer targets,the charge will be subjected to multiple impacts,the head is mainly compressed,and the tail will be repeatedly stretched and compressed to collide with the back cover of the projectile;during the penetration process,there will be a bottom gap between the charge and the back cover of the projectile and the gap is changed with the number of penetration layers.After the final penetration is completed,there is a plastic deformation on the charge and the internal bottom gap is existed.In this paper,the dynamic response mechanism of the charge projectile falling and penetrating into the multi-layer target plate is studied through numerical simulation,and further analysis is carried out in combination with experimental testing and theory,which lays an important foundation for the subsequent development of the test and design research of the charge projectile. |
