LONG-ROD PENETRATION, TARGET RESISTANCE, AND HYPERVELOCITY IMPACT

Numerical simulations are used to examine long-rod penetration as a fu nction of impact velocity. Similarities and differences between the pe netration histories are analyzed, including penetration and tail veloc ities, penetration depths, crater radii, centerline interface pressure s, and the extents of plastic flow in the projectile and target. The o ne-dimensional modified Bernoulli theory is often used to examine long -rod penetration into semi-infinite targets, and integral to the theor y is a term that describes the resistance of the target to penetration . It is observed that the target resistance decreases with impact velo city, and it is shown that this is a consequence of both the residual phase of penetration and variations in the size of the plastic zone fi eld.