ARMY BALLISTIC RESEARCH LAB ABERDEEN PROVING GROUND MD
Given a hit and specific target, the targets vulnerability depends upon the type of threat, for example, kinetic energy KE penetrator, shaped- charge jet or high explosive. This report addresses the threats associated with KE rod penetrators and shaped-charge jets. The questions studied are penetration capability, decreasing penetrator velocity and mass through the armor, hole- growth rate and hole size. The model is based on the conservation of mass and the equations of motion in both the radial and axial directions and is used to predict the time dependent penetration depth, penetration velocity, radial velocity imparted to the target, target hole profile, and the erosion of the penetrating projectile. Incompressible flow is assumed for the axial flow, but target-strength effects and viscous-shear effects are included in the analysis. Plugging of the target is not considered in the present model and all target flow is assumed to occur in the radial direction. This radial flow compressible but uniform is assumed to occur in three different regimes first, target material under the interface flows radially outwards primary regime, then, eroded penetrator forces additional radial flow of target material secondary regime, and finally, the radial inertial induced by primary and secondary flow is absorbed by the surrounding target material tertiary regime.