【摘要】 为研究埋头弹相较于常规弹膛内运动过程的差异，以某中口径埋头枪弹为研究对象，分别建立埋头弹与常规弹的膛内运动有限元仿真模型，利用幅值子程序VUAMP施加弹底压力，通过仿真模拟得到了两种枪弹在弹头形貌变化、弹头挤进阻力、弹头自转角速度、弹头导转侧力以及弹头被甲表面应力变化方面的差异。同时对埋头弹自动武器可能出现的弹膛偏移现象开展了研究。研究结果表明：与常规弹相比，埋头弹的长自由行程所带来的挤进阶段的强冲击使其被甲表面出现了更明显的塑性变形，表现为“梯形”刻痕，但最高膛压、初速与自转角速度都更低。在挤进阶段，埋头弹的导转侧力始终处于较高的水平。埋头弹较高的初始冲击速度使其弹头表面应力高于常规弹。对于弹膛偏移而言，随着弹膛偏移量的增加，埋头弹弹头表面结构完整性变差，挤进速度也呈减小趋势，弹头在膛内运动平稳性变差。由于弹膛偏移后埋头弹与枪管的碰撞降低了弹丸的挤进速度，导致弹后空间增加速率的减慢，弹丸的最高膛压、初速以及自转角速度增大。研究结果可为后续研究埋头枪弹在弹-枪相互作用、弹头的气动参数以及自动武器的设计方面提供参考。更多还原

【Abstract】 In order to study the difference of the motion process in the bore between the cased telescoped ammunition and the conventional projectile, taking a medium-caliber cased telescoped ammunition as the research object, the finite element simulation models of the in-bore motion of cased telescoped ammunition and conventional projectile were established respectively. By utilizing the amplitude subroutine VUAMP to apply the bottom pressure of the projectile, the differences between the two kinds of projectiles in the change of morphology, engraving resistance, and angular velocity, force on projectile’s driving side, and the stress change of the surface of the bullet jacket were obtained through simulation. At the same time, the phenomenon of chamber offset that may occur in the automatic weapon firingcased telescoped ammunition was studied. The results show that: compared with the conventional projectile, the strong impact of projectile engraving caused by the long free path of the cased telescoped ammunition causes more obvious plastic deformation on the surface of the bullet jacket, which is manifested as “trapezoidal” notch, but the maximum chamber pressure, muzzle velocity and angular velocity are lower. The force on projectile’s driving side of the cased telescoped ammunition is always at a high level during engraving. The higher initial impact velocity of the cased telescoped ammunition makes the surface stress of the bullet jacket higher than that of the conventional projectile. For chamber offset, with the increase of the offset of the chamber, the surfacestructural integrity of the projectile becomes worse. The engraving velocity also shows a decreasing trend, and the motion stability of projectile in the bore becomes worse. Due to the collision between the cased telescoped ammunition and the barrel caused by the offset of the chamber, the projectile’s engraving velocity is reduced, resulting in a decreased increase rate of the space behind the projectile, the maximum chamber pressure, muzzle velocity and angular velocity of the projectile are also increased. The study provides a reference for the further studies of the bullet-barrel interaction, the aerodynamic parameters of the projectile and the design of automatic weapons.更多还原