Analysis of the Impact of Inclined Grooves on the Interior Surface of Shaped Charge Liners on the Post-Penetration Damage Effects of Fragmentation Clouds

Abstract Due to the fact that traditional oxygen-free copper liners rely on the Monroe effect to generate a metal jet for penetrating target armor, resulting in the formation of a fragment cloud and residual jet particles post-armor penetration, which inflict damage on the target, there is a need to enhance the damaging effect of the metal jet after penetrating armor. In this regard, an internally inclined groove liner is designed based on the traditional oxygen-free copper liner. By varying the groove depth and quantity, the post-penetration effects are investigated using the Smoothed Particle Hydrodynamics (SPH) algorithm. The results indicate that increasing groove depth affects the maximum coalescence velocity of the fragment cloud. Furthermore, the number of inclined grooves is positively correlated with the maximum coalescence velocity of the fragment cloud and has a certain impact on the maximum fragment divergence angle. A complex relationship is observed between groove depth and average single-hole area, with variations at different depths, potentially influencing the area of small expansion holes. Differences are found in the average total single-hole area and maximum expansion hole area among different groove groups, notably in the widespread distribution of single-hole areas within the 8-groove group, potentially leading to greater unevenness in expansion hole areas. Numerical simulations and experimental results demonstrate that the liner with inclined grooves generates larger perforation areas compared to the intact liner, indicating enhanced lateral killing effects. The close agreement between experimental and numerical simulations suggests that the design of inclined grooves effectively enhances the post-damage performance of the liner.