A Scaling Technique to Predict Ballistic Limits

Abstract

Robust scaling techniques can be effective tools in the design of armour systems. Existing scaling models have traditionally involved fits to broad datasets that can be used to map out significant parametric variations, such as projectile geometry, mass, and yaw. In the present study, a semi-analytical model is developed to scale residual velocity data for a given projectile penetrating Kevlar fabrics. The premise of the approach is to scale the energy absorbed by the target material according to a deviation from an inertial model of penetration. A scaling parameter, independent of the number of Kevlar layers, is defined as a function of incident velocity. Using this scaling parameter, data for a 16 grain fragment penetrating an 8-ply, 1,000-denier Kevlar 29 is used to predict the residual velocity curves for 16-, 18-, and 22-ply Kevlar. Predictions of the ballistic limit are found to lie within 10% of the experimentally-determined ballistic limit.