Projectile shape influence on ballistic limit curves as determined by computational simulation

A requirement for an effective debris shield is that it must protect a spacecraft from impacts by irregularly shaped particles. A series of numerical simulations has been performed using the multi-dimensional shock physics code CTH to numerically determine the ballistic limit curve for a Whipple bumper shield. Two different projectile shapes are considered for the numerical simulations, flat plates of varying diameters with a constant thickness and spheres of varying diameters. The critical diameter or ballistic limit was determined over a velocity range from 4 km/s to 15 km/s. We have found both experimentally and numerically that the particle shape has a significant effect on the debris cloud distribution, ballistic limit curve, and penetration capability.