Permeability of textile fabrics with spherical inclusions

We investigated the effect of rigid spherical inclusions such as microcapsules and fillers on the permeability of fabrics by using glass beads as model inclusions. Beads with a range of diameters (40-800 μm) and volume fractions (2.5-10%) were sieved between layers of woven E-glass fabric targeting a fiber volume fraction of 40%. Permeability measurements were completed by X-ray microtomography to analyze the samples pore structure and estimate their permeability using Computational Fluid Dynamics simulations. Experimental and numerical estimates were also fitted with a Kozeny model accounting for porosity and specific surface of samples. We identified a threshold curve related to bead diameter and volume fraction below which the permeability follows that of a plain packed textile, and above which a strong departure from this trend is observed, induced by strong distortions of the textile. This behavior was closely correlated to the internal features of the textile.