Ballistic Strength of Kevlar KM2 Fabric Resisting FSP Projectiles

Abstract

A micro-level numerical tool, based on an explicit digital element approach (DEA), is developed to simulate impact and penetration of textiles using projectiles of arbitrary shapes. In this approach, the projectile surface is discretized into surface triangle elements and the fabric is discretized into digital elements. A special algorithm is employed to search contacts between digital elements of the fabric and surface elements of the projectile of arbitrary shape. In each simulation step, forces applied to projectile surface elements and digital elements are calculated. Then, projectile motions, such as velocity and acceleration, can be calculated based on the resultant force applied to projectile surface elements and the fabric deformation can be calculated based upon the force applied to digital elements. In the previous DEA analysis, the projectile was simplified as a rigid body particle. As such, only spherical and cylindrical projectiles could be modeled. The new Algorithm proposed in this paper expands the capability of the DEA to simulate ballistic impact using projectiles with arbitrary shapes. In this paper, the contact search algorithm and the contact force calculation between the solid body projectile and the fibrous fabric are explained in detail. Firstly, the surfaces of spherical and RCC projectiles are discretized into triangle meshes. Ballistic strength V50 derived from the discretized surface mesh are compared to results derived from the previous approach in order to verify the accuracy of the method. Then, the new algorithm is applied to simulate the ballistic impact using FSP the projectile. The numerical results are compared to real scale standard ballistic tests using FSP.