Homogenization of Fickian and non-Fickian water diffusion in composites reinforced by hydrophobic long fibers: application to the determination of transverse diffusivity

Abstract The present paper investigates the water absorption by polymeric matrix composites at both microscopic ( i.e. reinforcements are explicitly depicted) and macroscopic ( i.e. homogeneous media) scales through a numerical homogenization method. In this work, the two linear diffusion Fick’s and Langmuir’s laws are considered. The effective transverse diffusivities of Uni-Directional laminates are computed with the help of the Finite Element Method and compared to both analytical models and experimental data. The impact of the distribution of the hydrophobic reinforcements within the matrix is also pointed out.