基于SPH的椭圆双极线性聚能药包控制爆破数值模拟研究

Numerical analysis of controlled blasting of elliptic bipolar linear shaped charge based on SPH

为了优化椭圆双极线性聚能药包爆破参数,基于光滑粒子流体动力学方法(SPH),研究了聚能装药聚能射流的形成并与已有试验及模拟做对比,验证所实现SPH方法的有效性,再基于SPH和相同参数及本构方程研究椭圆双极线性聚能药包爆破射流形成机理,分析外壳和药型罩对椭圆双极线性聚能药包爆破聚能射流的影响。结果表明:椭圆双极线性聚能药包通过压垮药型罩形成聚能射流,聚能射流形成的同时爆生气体不断撞击外壳向非聚能方向运动,变形到达一定程度之后外壳与药型罩连接部位断开,外壳与药型罩连接部位断开后溢出的爆生气体速度大于射流头部速度;外壳对椭圆双极线性聚能药包射流头部速度有一定影响,随着外壳厚度不断增大,射流头部速度也在增大,且不同外壳厚度的聚能药包射流头部速度随时间变化趋势趋于一致,外壳越厚越利于稳定爆轰,从而利于射流的形成,射流速度越大;当外壳厚度一定时,药型罩厚度不断减小,爆生气体用于压垮药型罩做的功越少,转换为聚能射流动能越多,聚能射流头部速度越大;当无药型罩时,无法形成明显射流,表明药型罩对聚能射流的形成起决定作用;药型罩和外壳的共同作用下使得聚能射流的效果更佳。数值分析结果对优化椭圆双极线性聚能药包爆破具有一定的指导意义。

In order to optimize the blasting parameters of elliptic bipolar linear shaped charge,based on the smooth particle hydrodynamics method(SPH),the formation of shaped charge jet is studied and compared with the existing experiments and simulations to verify the ef⁃fectiveness of the SPH method.Then based on the SPH and the same parameters and constitutive equations,the formation mechanism of the jet is studied and the influence of shell and liner on the jet of elliptical bipolar linear shaped charge is analyzed.The results show that the elliptical bipolar linear shaped charge forms the shaped charge jet by crushing the liner shaped charge,and the explosive gas continu⁃ously impacts the shell and moves towards the non concentrated energy direction when the shaped charge jet forms.When the deformation reaches a certain degree,the connection part between the shell and the liner is disconnected,and the explosive gas velocity overflows after the connection part between the shell and the liner is disconnected is greater than the jet head velocity;The shell has a certain influence on the jet head velocity of elliptical bipolar linear shaped charge.With the increasing thickness of the shell,the jet head velocity is also in⁃creasing,and the jet head velocity of shaped charge with different thickness of the shell tends to be the same with time.The thicker the shell is,the more stable detonation is,which is conducive to the formation of jet,and the greater the jet velocity is;When the thickness of the shell is fixed and the thickness of the liner decreases continuously,the less work the explosive gas does to crush the liner,the more ki⁃netic energy is converted into the concentrated jet,and the faster the head velocity of the concentrated jet is.When there is no liner,no jet can be formed,which shows that liner plays a decisive role in the formation of jet;Under the joint action of the liner and the shell,the effect of the jet is better.The results of numerical analysis have certain guiding significance for the optimization of elliptic bipolar linear shaped charge blasting.