EFP构型对其气动特性和侵彻性能影响分析

Analysis of the influence of EFP configuration on its aerodynamic characteristics and penetration performance

为综合分析爆炸成型弹丸(explosively formed projectile,EFP)的构型对其气动特性和侵彻性能的影响,实现兼具良好气动特性和侵彻性能的EFP设计。开展了EFP的成型和飞行试验,在试验验证数值有效性的基础上,基于任意拉格朗日欧拉(arbitrary Lagrange-Euler,ALE)算法分析了后翻型EFP的三种典型构型(实心杆状、小空腔状、大空腔状)的成型过程及气动特性,并进一步开展了三种构型EFP侵彻半无限厚45#钢的数值模拟。结果表明:EFP小空腔结构提高了其飞行稳定性;空腔的增大降低了EFP的存速能力,实心、小空腔、大空腔三种构型的EFP炸高在1000倍弹径(30 m)时平均速度降分别为158 m/s,172 m/s,210 m/s;随着EFP空腔的增大,靶板开坑形貌由漏斗状逐渐转为等直径状。从工程实践角度设计EFP构型时:对于近距离目标应选取实心型;对于远距离目标应选取小空腔型。

In order to comprehensively analyze the influence of configuration of explosively formed projectile(EFP)on its aerodynamic characteristics and penetration performance,an EFP design with good aerodynamic characteristics and penetration performance was realized.The forming and flight tests of EFP were carried out.On the basis of verifying the numerical validity,the forming process and aerodynamic characteristics of three typical configurations of back-ward-turned EFPs(solid rod,small cavity,and large cavity)were analyzed based on the arbitrary Lagrange-Euler(ALE)algorithm,and the numerical simulation of three configurations of EFPs penetrating semi-infinite thick steel were further carried out.Results show that the small cavity structure of EFP improves its flight stability;the increase of cavity reduces the storage capacity of EFP,and the average velocity decrease of the three types of small-caliber EFPs are 158 m/s,172 m/s,and 210 m/s at 1000 times the projectile diameter,respectively;with the increase of EFP cavity,the pit shape of the target plate will gradually change from funnel-shaped to equal-diameter shape.When designing EFP configuration from the perspective of engineering practice,solid type should be selected for short-range targets and small cavity type should be selected for long-range targets.