Nonuniform fiber networks and fiber-based composites: Pore size distributions and elastic moduli

摘要

An excluded-volume approach is developed for modeling the distribution of pore sizes and the specific surface area in isotropic networks of cylindrical fibers. The effect of accounting for nonuniformities in the spatial distribution of the fibers upon the mean pore size and effective surface area is examined. Fluctuations in the fiber volume fraction are shown to increase the mean pore radius and to reduce the specific surface area relative to their values for a spatially uniform network. A method is suggested for addressing the impact of spatial nonuniformities in the fiber volume fraction within mean-field and semiempirical models for the elastic moduli of fiber-based composites.