Finite element modeling of longitudinal permeability component of a stitched fabric

The following work aims to present a reliable numerical method for predicting the longitudinal permeability of a unidirectional (UD) stitched fabric. An experimental measurement of longitudinal permeability is done using a closed resin transfer mold (RTM) system. Concerning the Finite element modeling, an arrangement of the fiber bundles and a unit cell is proposed. The evaluation of numerical permeability is based on a main assumption. The assumption says that the permeability of the unit cell is mainly calculated from the flow passing through gaps (between the bundles). Thus we avoid the simulation on a real unit cell with micro flow throughout the fibers. The predicted numerical results were in good agreement with the experimental data.