Rigid Penetrators

Abstract

This chapter discusses the penetration process of rigid penetrators into semi-infinite targets. This is the basic science behind the field of penetration mechanics. We start with the basic question regarding the nature of deceleration of a rigid projectile, and use both empirical data and numerical simulations to show that this deceleration is constant throughout the penetration process, independent on the projectile’s impact velocity at the ordnance range. At higher velocities, beyond a certain threshold, the inertia of the target sets in and the deceleration becomes velocity dependent. This issue is treated numerically, as is the effect of the entrance phase on the penetration process. Numerically-based analytical models are developed for these phenomena and are shown to account for the corresponding empirical results. We discuss the penetration of concrete targets by rigid projectiles. This process is also governed by a constant-deceleration of the projectile. The non-scaling phenomenon of penetrations into concrete targets is accounted for by a simple model. The transition from rigid to deforming-rod penetration is presented and accounted for by analytical considerations. Finally, the effect of yaw on the penetration of rigid projectiles is treated numerically.