Implementation of a Mesomechanical Material Model for IAD Fabrics within LS-DYNA

The implementation and evaluation of a high fidelity material model for dry fabrics is the main objective of this paper. Inflatable Aerodynamic Decelerators (IADs) and other airinflated structures quite often utilize woven fabrics due to their lightweight and high loading carrying capabilities. Design optimization of these inflated structures relies on a detailed understanding of the woven fabric mechanics. Woven fabrics are composite orthotropic materials that respond differently under load from traditional solid mechanics. While lowfidelity fabric materials usually assume a continuous medium, a higher fidelity model needs to account for the reorientation of yarns and weave geometry. An existing mesomechanical material model within the LS-DYNA  commercial non-linear finite element software package is utilized. In this paper, experimental stress-strain data for Kevlar  129 samples are validated against numerical simulations of models with matching geometry and loading conditions.