International Journal of Impact Engineering 33 (2006) 143–157 Damage-potential comparison of spherical and cylindrical projectiles impacting on a system of bumper plates C. Carrasco , O. Melchor-Lucero, R. Osegueda, L. Espino, A. Fernandez FAST Center for the Structural Integrity of Aerospace Systems, The University of Texas at El Paso, El Paso, TX 79968-0698, USA Available online 7 November 2006 Abstract This paper describes a series of smooth particle hydrodynamics (SPH) simulations of tungsten cylindrical and spherical projectiles impacting steel bumper plates at different impact configurations. Comparisons of the destructive capabilities of the spherical and cylindrical projectiles for each impact configuration are presented. Cylindrical geometries were spatially rotated to cover a wide range of impact configurations. The incidence angle of the velocity vector and its magnitude were varied. A rational approach is proposed to quantify the level of damage inflicted on the bumper plates on each impact event. This damage measure is used to create a set of comparative damage matrixes for cylindrical and spherical projectiles that identify under which impact configurations a given geometry is more damaged than the other. r 2006 Elsevier Ltd. All rights reserved. Keywords: Damage comparison; Projectiles; Bumper plates 1. Introduction An in-depth understanding of the interplay of the parameters that control the damage generated by projectiles traveling at high velocity is of significant importance for aerospace and military applications. In real impact scenarios, the shape and impact geometry can vary considerably. When shape and geometry are combined with relatively complicated targets, it is often difficult to determine which impact conditions are the most damaging. Numerical simulations are used to investigate damage caused by difference in projectile shape and aspect ratio, and impact conditions as a function of impact speed. The complicated target is represented by a multiple plate array. A metric of damage is developed so that comparisons can be made as a function of geometry and impact conditions. 2. Overview of recent penetration mechanics work A comprehensive comparative analysis of the damage potential of different shapes of projectiles for a wide range of impact configurations is not available in the literature. There has been an extensive study of the penetration characteristics of spherical projectiles for different impact velocities, obliquity velocity angles and ARTICLE IN PRESS www.elsevier.com/locate/ijimpeng 0734-743X/$ - see front matter r 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.ijimpeng.2006.09.074 Corresponding author. Tel.: +1 915 747 6919; fax: +1 915 747 8037. E-mail address: ccarras@utep.edu (C. Carrasco).