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This study focuses on developing a global/local three-dimensional (3D) finite element model of a Kevlar KM2 Õ plain woven fabric applicable for examining ballistic impact from a spherical projectile. The impact event is modeled in LS-DYNA Õ including friction between the individual yarns as well as the projectile and fabric. When compared with the predictive capabilities of a 3D finite element model that includes the detailed undulating representation of the fabric architecture over the entire solution domain, the savings in computational effort afforded by the global/local model become especially attractive. The agreement with fully detailed 3D finite element simulations and ballistic experiments is also demonstrated.

The focus of this study is aimed at characterizing the weave architecture in orthogonally woven polymer and ceramic—matrix composites. Three-dimensional (3D) geometric models of the unit-cells of four harness (4HS), five harness (5HS), and eight harness (8HS) satin weave morphologies are developed. The fiber bundle and matrix architecture in the 4HS, 5HS, and 8HS morphologies is represented via mathematical shape functions within the domain of the repeating unit-cells of the woven fabrics. This work brings together the non-uniform layer methodology of Kuhn and Charalambides [1] and the sub-cell modeling approach developed by Hewitt et al. [2]. In addition, this article introduces the novel concept of a `middle matrix layer' in capturing the ingress of matrix material away from undulating bundle regions, as documented by Morscher [3]. The geometry models developed herein account for a porous polymer matrix deposited over the woven mat via either resin film infusion (RFI) or resin transfer molding (RTM). This modeling also incorporates micro-structural intricacies observed in woven CMCs fabricated using chemical vapor infiltration (CVI) techniques for the deposition of the ceramic—matrix phase. Finally, results on the overall volumetric composite characteristics are reported.

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