Numerical modeling of the flax fiber morphology variability

This paper provides a methodology for the numerical modeling of the scattering observed in the geometry of plant fiber cross-sections. It is well known that the observed random microstructures are expected to have a significant impact on the calculation of their effective properties. The solution proposed here to model randomness in the fiber boundary contour, which has never been done in the past to the author's knowledge, is based on a randomized version of the Fourier expansion of its complex coordinate function. The involved random variables have been identified from a large set of 2D optical micrographs and the methodology has been applied both to elementary fibers and bundles which are simultaneously observed on composite sections. This model is found to be sufficiently relevant to render the morphometric factors of the observed fibers in a statistical sense. This contributes to the microstructural modeling of composites reinforced by natural fibers.