贮箱爆炸碎片初始速度及影响因素

为确定推进剂爆轰作用下贮箱爆炸碎片的初始速度，基于能量守恒定律，考虑爆炸碎片动能、爆轰产物动能和内能、贮箱壳体的破坏能及其膨胀做功所消耗的能量，建立了贮箱爆炸碎片初始速度（FIV）模型。FIV模型与典型经验公式计算结果、带壳炸药爆炸试验数据吻合较好，验证了模型有效性。采用量纲分析法确定FIV模型中影响碎片初始速度的关键参量，基于AUTODYN软件进行数值仿真，分析贮箱壳体高径比、厚径比以及空气密度等参量对碎片初始速度的影响。结果表明:爆炸碎片初始速度随着壳体高径比增大迅速减小，当高径比大于1.50时，速度衰减变缓；碎片初始速度随着壳体厚径比增加近似呈线性减小；当爆炸高度小于20 km时，随着爆炸高度增大，空气密度减小，爆炸碎片的初始速度增大；在爆炸高度大于40 km时，空气非常稀薄，可以忽略壳体膨胀做功对碎片初始速度的影响。 

Initial velocity and influence factors of tank explosion fragments

To determine the initial velocity of tank explosion fragments under the propellant detonation, the fragment initial velocity (FIV) model was established based on the energy conservation law, in which the kinetic energy of explosion fragments, the kinetic energy and internal energy of detonation products, the failure energy and the consumed energy for expansion work of tank shell were considered. The FIV model was in good agreement with the calculation results of typical empirical formulas and the experimental data, which verifies the effectiveness of the model. Based on the dimensional analysis method, the key parameters affecting the initial velocity were determined. Based on AUTODYN software, numerical simulation was conducted and the effects of height-diameter ratio, thickness-diameter ratio and air density on fragment initial velocity were analyzed. Results show that the initial velocity of explosion fragment decreases rapidly with the increase of height-diameter ratio, and the attenuation trend slows down when the height-diameter ratio exceeds 1.50. The initial velocity almost linearly decreases with the increase of thickness-diameter ratio. When the explosion height is less than 20 km, as the explosion height rises, the air density decreases, and the initial velocity increases. The air becomes very thin above 40 km, and the influence of shell expansion work on initial velocity can be neglected.