Computational model for woven fabrics subjected to ballistic impact by a spherical projectile

We present a numerical model that simulates ballistic impact of a rigid spherical projectile into a plain weave fabric target. The code, which runs in MATLAB on a highend PC or laptop, allows one to vary projectile radius, mass and velocity, as well as various fabric mechanical and geometric parameters. These include yarn spacing, stiffness and density, non-linear slip viscosity between fabric and projectile, non-linear viscoelastic contact stiffness (compressibility) at yarn crossovers together with viscoelastic shear stiffness resisting yarn sliding, and the angle of yarn crimp out-ofplane. The model accommodates a progressively spreading contact zone on the fabric, as occurs with an impacting spherical projectile. Fabric dimensions are chosen large enough to avoid any tension wave reflections at the boundary. After providing some details on the finite difference formulation of the model, we present a sampling of results obtained at various times after impact. The results include contour plots of out-of-plane displacements, out-of-plane and in-plane velocities and yarn strain distributions at a given time, as well as plots, over time, of maximum local strain level, and out-of-plane velocities and displacements in the contact region of the projectile. Some parameters will be varied to provide insight into the rich behavior possible.