高超音速侵彻混凝土过程中侵彻弹体装药塑性安定性分析

Plastic Charge Stability Analysis of Supersonic Projectile During Penetration of Concrete Targets

尽管侵彻动力学研究有大量的研究报道,但是主要集中于弹体结构响应和侵彻能力研究,涉及侵彻体内部装药安定性的研究较少,而且没有形成系统的装药安定性理论分析方法。本文根据弹体内部装药的塑性应力-应变本构关系,首次提出了利用弹体结构与内部装药相对位移、摩擦功、热力学原理和热点理论推导的装药热安定性结构设计塑性理论分析方法。研究过程中从空穴膨胀理论出发确定侵彻弹体的响应函数,结合牛顿第二定律,采用有限差分技术获得弹体侵彻过程的轴向阻力和惯性过载。以弹体惯性过载作为装药安定性响应的输入,通过理论分析确定弹体壳体与内部装药界面热影响区内炸药温度上升情况,分析表明:内部装药过载系数、装药长度是影响装药安定性的重要因素,而且热影响区内炸药温度上升沿装药轴线呈现非线性变化。此外,如果装药直径给定,通过计算可以确定热影响区内炸药温度上升的最大值及其发生位置。理论分析结果给出了能够定量描述装药安定性结构设计的物理参数和几何参数,可以作为装药安定性结构设计的重要依据和参考。

Even though there are extensively studies on penetration dynamics,these studies mainly focused on the structure response and penetration depth of projectile.Almost no charge stability theory theoretical analysis method in the process of penetration has yet been reported.This paper derived a novel theoretical analysis method of charge stability in the process of penetration,which is based on the assumption of plastic stress-strain deformation relationship of main charge,friction work,principle of thermal dynamics.The resistance function during penetration is based on the cavity expansion theory,using mass and monument equation,Hugoniot jump condition.The resistance forces are calculated with finite difference method and Newton′s Second law.The temperature rising between explosive-casing interfaces due to friction can be estimated with the input resistant force function.The novel theory shows that charge stability strongly depends on the maximum length of charge and overload characteristic of charge.In addition,the location of maximum temperature rising can be determined if the diameter of charge is given.The analytical results of this study provide the physical and geometry parameters,which can used as an important reference of charge design.