基于爆炸成型弹丸(EFP)的大锥角喇叭罩成型规律

Formation Characteristics of Trumpet-shaped Liner with Large Cone Angle Based on Explosively Formed Penetrator(EFP)

为了进一步拓展适用于爆炸成型弹丸(EFP)的药型罩结构,基于弧锥结合罩结构,提出了一种可形成密实EFP的大锥角喇叭罩。根据药型罩结构特点,分析了大锥角喇叭罩与传统弧锥结合罩和球缺罩在压垮过程中的区别和特点;运用LS-DYNA数值模拟软件,计算得到了大锥角喇叭罩的结构参数(虚拟罩高、喇叭曲率半径、圆弧曲率半径和罩厚)对EFP侵彻体速度、长度、密实度等成型参数的影响规律。结果表明,大锥角喇叭罩罩厚对侵彻体的影响主要体现在头部速度,虚拟罩高和圆弧曲率半径则决定了侵彻体长度及密实度,而喇叭曲率半径则主要影响侵彻体头部的成型状态;与传统弧锥结合罩和球缺罩形成的EFP相比,相同质量的大锥角喇叭罩形成的EFP在头部速度、长度、长径比及密实度等方面均具有一定优势,可将侵彻体密实度提高1~3.5倍,具有应用于EFP战斗部的潜力;其适用于较佳EFP成型时各结构参数的取值范围为:虚拟罩高0.14~0.16倍装药直径,喇叭曲率半径1.5倍装药直径以上,圆弧曲率半径0.4~0.8倍装药直径,罩厚0.04~0.045倍装药直径。

To further improve the liner structure applicable to explosively formed penetrator(EFP),the trumpet-shaped liner with large cone angle was proposed based on the arc-cone liner structure.On the basis of structural features of liner,the difference in collapse process for the trumpet-shaped liner with large cone angle with the traditional arc-cone liner and hemispherical liner was analyzed.The influencing pattern of trumpet-shaped liner structural features(virtual height,trumpet curvature,arc curvature,and thickness of liner)on formation parameters of tip velocity,length and compactness,were calculated by LS-DYNA simulation software.The results show that the thickness of trumpet-shaped liner directly influences EFP tip velocity,and virtual height and arc-section curvature of trumpet-shaped liner squarely influences length and compactness of EFP,while tip formation of EFP is determined by the curvature of trumpet-section liner.Compared with conventional arc-and-cone-shaped liner and sphere-segment-shaped liner,the EFP formed by trumpet-shaped liner with large cone angle has certain advantages in tip velocity,length,length-diameter ratio and compactness,which can increase the compactness of penetrator by 1-3.5 times.it can produce more desirable compact EFP on the condition of virtual liner height equals to 0.14 to 0.16 times shaped charge diameter,trumpet-section curvature equals to more than 1.5 times shaped charge diameter,arc-section curvature equals to 0.4 to 0.8 times shaped charge diameter,and liner thickness equals to 0.04 to 0.045 times shaped charge diameter.