Effects of nesting and laminate misalignment on resin permeability of woven composites: Analysis using a homogenization method

Abstract

In this study, the effects of nesting and laminate misalignment on the resin permeability of woven composites are investigated using an asymptotic homogenization method for permeation flow. For this, a meso-scale unit cell model consisting of two hexagonal prisms with four fiber bundles and periodic boundary conditions for the unit cell are proposed to explicitly consider the nesting and laminate misalignment. This method enables to deal with arbitrary amounts of nesting and laminate misalignment easily, which has been difficult in the case of using conventional cuboid unit cells. The unit cell and boundary conditions are then applied to the homogenization method for permeation flow, and resin permeability analysis of plain-woven glass fiber-reinforced plastic (GFRP) composites are conducted. It is shown from the results that the nesting affects the mesoscopic characteristic flow velocity and the macroscopic resin permeability, and that they tend to decrease with increase in nesting. It is also shown that the laminate misalignment significantly affects the distribution of mesoscopic characteristic flow velocity and the macroscopic resin permeability, and that a combination of nesting and laminate misalignment can successfully reproduce experimentally observed macroscopic resin permeabilities of plain-woven GFRP composites.