Abstract:
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 effectiveness 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 continuously 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 increasing, 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 kinetic 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.