A 3D voxel-based mesostructure generator for finite element modelling of tow-based discontinuous composites

Tow-based discontinuous composites manufactured with ultra-thin tapes display high stiffness, strength, and in-plane isotropy, thus competing with composite laminates. Their complex 3D microstructure affects the mechanical response, in turn demanding 3D generators that capture the tape waviness, resin pockets, and thickness and fibre content variations. The present work proposes an automated numerical framework combining a 3D voxel-based mesostructure generator with finite element models. A modified 3D random sequential absorption technique is developed with bin-guided allocation, draping, and thickness control. A statistical study is used to size the statistical volume elements and predict the elastic properties of thick, thin, and ultra-thin tow-based discontinuous composites. The results are compared with the experimental values from the literature. Despite uncertainties in physical tape properties, the resulting stiffnesses are predicted with good accuracy.