起爆方式对椭圆截面战斗部破片速度分布的影响

Effect of initiation models on the fragment velocity distribution of elliptical cross-section warhead

为研究椭圆截面战斗部在不同起爆方式下破片速度的分布特性,建立了5种具有不同短长轴比的椭圆截面战斗部数值模拟模型。开展了端面中心单点、短(长)轴中点双点、短长轴中点4点以及端面面起爆5种起爆方式数值模拟研究,分析了不同起爆方式下椭圆截面战斗部破片的速度分布及能量输出特性。研究结果表明:在径向方向,战斗部在不同起爆方式下破片最大径向速度变化规律基本一致,均呈现由长轴至短轴方向对数增长,且随着短长轴比的增大,短长轴方向破片速度差值逐渐减小。然而,不同起爆方式下椭圆截面战斗部最大速度截面上破片速度平均值存在明显差异,具体表现为端面起爆时的破片径向平均速度最高,单点起爆最低,且随着起爆点数量的增加,最大速度截面上的破片的整体平均速度逐渐增大。在轴向方向,受端面稀疏波的影响,不同方位角最大破片速度均出现在靠近非起爆端1/4处,且起爆点在短轴轴线上相较于在长轴轴线上会提高靠近起爆端长轴方向的破片速度,但短轴方向沿轴向的破片速度分布无明显差异。此外,不同起爆方式对椭圆截面装药爆炸能量输出特性无明显影响,其中27%的装药能量转化为壳体动能,有50%的能量被壳体断裂变形以及空气冲击波消耗。

To investigate the velocity distribution characteristics of elliptical section warhead(ECSW)fragments under different initiation modes,a numerical simulation model was established for five ECSWs with different shape ratios.Numerical simulations were conducted to investigate the velocity distribution and energy output characteristics of fragments from ECSW under five different initiation modes:central single-point initiation,dual-point initiation at the midpoint of the minor(or major)axis,four-point initiation at the midpoint of the major and minor axes,as well as surface-initiated detonation.The research findings suggest that the maximum radial velocity of fragments follows a consistent logarithmic growth pattern in the radial direction across various initiation modes,increasing from the major axis to the minor axis direction.With an increase in the shape ratio,the difference in fragment velocities between the major and minor axis directions gradually decreases.However,the maximum velocity profiles of fragments from elliptical section warheads exhibit noticeable differences in average velocities under different initiation modes.Surface-initiated detonation produces the highest average radial velocity,whereas single-point initiation leads to the lowest.As the number of initiation points increases,the overall average fragment velocity on the maximum velocity profile gradually rises.In the axial direction,the influence of rarefaction waves leads to the maximum fragment velocities occurring near the 1/4 position from the non-initiating end at different azimuthal angles.Initiation points along the minor axis enhance the fragment velocity in the major axis direction near the initiating end compared to initiating points along the major axis.However,there are no significant variations in the axial velocity distribution of fragments in the minor axis direction.The different initiation modes have negligible effects on the energy output characteristics of elliptical section charges.Approximately 27%of the charge energy is converted into shell kinetic energy,while 50%is dissipated through casing fracture deformation and air shock wave propagation.