Mesh Convergence Study for the Mesoscopic Analysis of a Triaxial Braided Carbon Fiber Reinforced Polymer Under Uniaxial and Shear Loading States

Abstract

In this study, the mechanical behavior and convergence of a finite element model of a carbon-fiber reinforced polymer (CFRP) composite with different mesh sizes are analyzed. A representative volume element (RVE) of a single-ply triaxially braided carbon fiber-epoxy composite is developed for this study. The model is subsequently meshed with periodic boundary conditions using the voxel meshing method. Numerical simulations of these models subject to uniaxial tension and shear are conducted using a commercial finite element (FE) code, Abaqus, to determine the in-plane mechanical properties of the polymer composite. To examine the corresponding convergence behavior, various mesh sizes are employed in RVE models generated. The models are compared based on their computational efficiency at a converged mesh size. It was determined that a medium sized domain length with an element length of approximately 0.1 mm is adequate to reach a converged solution with the shortest simulation time. The work provides a systematic mesh convergence examination of a popular meshing technique used in finite element analysis, which elucidates the optimal method to analyze this quasi-isotropic material in a streamlined fashion and paves an understanding of the advantages and limitations of this modeling approach. This analysis can be extended in future studies as a larger mesh convergence study that compares meshes with different geometric elements, such as 10-node tetrahedral element. The results of this study can also be used to simulate a larger continuum-sized composite material, in which computational efficiency is crucial.