A filament-level analysis on failure mechanism and ballistic limit of real-size multi-layer 2D woven fabrics under FSP impact

This paper investigates the failure mechanism and fabric ballistic performance of real-size multi-layer 2D woven fabrics impacted by sharp-edge fragment simulating projectile (FSP). First, the relations between digital fiber shear force and bending rigidity are established under the modified digital element approach (DEA) framework. Then, a systematic parametric study was carried out on the ballistic impact of a 4-inch-long single yarn and 4-inch by 4-inch 2D woven fabric at near fiber level to solve for the relations of digital fiber moment of inertia and ballistic limit. The results show that for the same number of digital fibers per yarn model, the simulated ballistic limits are in direct proportion to digital fiber moment of inertia. The increase of the number of digital fibers per yarn, however, decreases the digital fiber moment of inertia effect on ballistic limits. Second, the 1- to 28-layer real-size 2D woven Kevlar KM2 fabrics are simulated at filament level against FSP on the cluster to estimate the V50 zone. The perforation process and failure mechanism of 4-layer fabric is investigated and analyzed in detail. The simulation results demonstrate the deformed fabric shape with respect to time and the damage modes at the impact area. Numerical results are compared with standard ballistic test results.