Modeling the role of friction during ballistic impact of a high-strength plain-weave fabric

In order to examine the role of friction during ballistic impact of high-strength fabric structures, a commercially available finite element analysis code (LS-DYNA) was used to model the ballistic impact of a rigid sphere into a square patch of plain-weave fabric. Two types of boundary conditions were applied on the fabric: four edges clamped and two opposite edges clamped. Simple Coulomb friction was introduced between yarns at crossovers and between the projectile and the fabric. Modeling results show that the friction contributed to delaying fabric failure and increasing impact load. The delay of fabric failure and increase of impact load allowed the fabric to absorb more energy. Results from the modeling effort also indicate that fabric boundary condition is a factor that influenced the effect of friction. The fabric more effectively reduced the projectile residual velocity when only two edges were clamped.