Unsaturated flow in compressible fibre preforms

The isothermal infiltration of compressible fibre preforms was modelled taking into account the gradual saturation of the porous medium and the fibre tows. Similarities between this and drainage/imbibition processes, led to the adaptation of a finite-element code originally developed for soil mechanics. The dual scale of the porous medium was accounted for by considering delayed radial flow into the fibre tows. The chosen case study materials were polypropylene transversally infiltrating glass fibre mats. Local preform strain and stress profiles, as well as micro and macro-saturation, and local matrix pressure profiles were obtained. The influence of numerical and material parameters is discussed in relation to experimentally observed phenomena.