INVESTIGATION OF THE IMPACT OF A POROUS TUNGSTEN IMPACTOR WITH A COMBINED BARRIER

Abstract

With high-speed penetration (with velocities more than 2000 m/s), the length of the cavity from a porous striker is greater than from a striker of monolithic (solid) material equal to it in size and density. But at the same time the cavern is narrower, so the volumes of the caverns are almost the same. The process of length reduction and penetration of the strikers (porous and monolithic) for a long time occurs almost identically and only at the last stage of penetration and, especially in the aftereffect phase (after the complete destruction of the striker), there is a difference. This is explained by the fact that during the movement of the porous striker, due to the collapse of the pores, an increase in density occurs, so that the density of the porous striker becomes greater than the density of the solid striker. Then, in the case of a limited thickness of the barrier, the advantage of a porous striker in terms of penetration depth may simply not have time to manifest itself. The results of experiments conducted to confirm this assumption are presented below. The results of experiments on the collision of a porous tungsten impactor with a combined barrier consisting of a steel and polyethylene plate are presented, and the results are analyzed. The problem of numerical simulation of the above experiment by a mesh-free Lagrangian continuous medium modeling method is solved. The calculation model, the results of numerical modeling and a comparative analysis of the results of the experiment and numerical modeling are presented. At the penetration rate V ? 1920 m/s, the porous striker is 2.8% less destroyed when a strong steel barrier is broken through, but in a low-strength polyethylene barrier, the length reduction coefficient of the porous striker is 170% higher relative to the steel one. In addition, a steel striker after breaking through an obstacle (in the air) it does not collapse, unlike porous, which may also be a consequence of the low strength of the latter.