Numerical investigation of the application of voxel based meshes for stochastic tow based discontinuous composites

Abstract

Stochastic tow based discontinuous composites (STBDC) are fabricated from compression molding chips of chopped and slit pre-impregnated uni-directional carbon fiber reinforced polymer (CFRP) tape. The discontinuous mesostructure gives the material system increased moldability versus continuous fiber composites; however, this gives the material highly variable effective properties. For applications in finite element analysis, the mesostructural morph ology of STBDCs can be idealized using a non-conforming voxel-based mesh framework. The objective of this study is to investigate the effect of mesh coarsening on the elastic response of STBDC simulations. Furthermore, a method for the homogenization of the voxel based mesostructure is considered, with results compared against detailed simulations of the mesostructure. The results demonstrate that coarse mesostructures provide similar effective properties and internal stress distributions as detailed models. Furthermore, simulations with homogenized properties provide nearly identical results to detailed simulations for a fraction of the simulation time. • Voxel-based representative volume elements can be used to generate finite element models and calculate effective properties. • Chips size influences the magnitude of internal stress concentrations observed in representative volume elements. • Method for homogenization provides a similar elastic response as detailed representative volume elements. • Simulations capture the chip size effects on the effective modulus.