杆式弹对厚壁壳体装药冲击起爆机制模拟分析

为研究高速杆式弹冲击厚壁壳体装药的起爆机制，运用冲击物理显式欧拉型动力学SPEED软件，开展了不同弹径和弹长的钨合金杆式弹与厚壁壳体Comp-B装药相互作用过程的数值模拟，采用升降法获得弹体起爆装药临界着速及装药起爆位置变化。研究结果表明:弹体起爆装药临界着速随弹径增大而显著降低，随弹长增大呈先降低后平缓变化的规律；弹体以临界着速起爆装药时，存在2种装药起爆机制，即弹体贯穿壳体后的宏观剪切起爆和未贯穿壳体的低速冲击起爆，且其机制随弹体着速在临界着速以上继续提高会发生转变，最终均会转变为高速冲击起爆机制；装药起爆位置均发生在炸药壳体交界面后一定距离处，相同机制下此距离随弹体着速提高而减小。

Simulation analysis on the initiation mechanism of the explosive charge covered with a thick shell impacted by a rod projectile

In order to study the initiation mechanisms of the explosive charge covered with a thick shell impacted by a high- velocity rod projectiles, the shock physical explicit Eulerian dynamic software SPEED was applied to numerically simulate the interactions beween the tungsten rod projectiles with different diameters and lengths and the Comp-B charge covered with a thick shell, the up-down method was used to obtain the critical impact velocity and the change of the detonation position, and the effects of the projectile diameter and length on the critical impact velocity were obtained. The initiation mechanisms of the Comp-B charge detonated by the projectile at the critical impact velocity were analyzed in depth, and the effects of the projectile impact velocity on the initiation mechanism and the detonation position were obtained. The research results show that the critical impact velocity decreases significantly as the projectile diameter increases, the critical impact velocity first decreases and then gradually changes as the projectile length increases. When the Comp-B charge is detonated by the projectile at the critical impact velocity, there are two initiation mechanisms, namely the macro-shear initiation mechanism after the projectile penetrates the shell and the low-velocity impact initiation mechanism without penetrating the shell. The mechanisms will transform as the projectile impact velocity continues to increase above the critical impact velocity. If the macro-shear initiation mechanism dominates when the Comp-B charge is detonated by the projectile at the critical impact velocity, it will transform into the high-velocity impact initiation mechanism; if the low-velocity impact initiation mechanism dominates at this time, it will first transform into the macro-shear initiation mechanism, and then transform into the high-velocity impact initiation mechanism. The detonation position is at a certain distance from the interface between the explosive and the shell, the distance decreases as the impact velocity of the projectile increases if the initiation mechanism remains the same.