Experimental and Numerical Analyses of the In-plane Permeability of 2.5D-woven Carbon Fabric Preforms with Compressive Deformation

The radial flow method is applied to obtain the in-plane permeability of a kind of 2.5D-woven carbon fabrics with various compression ratios. Geometrical parameters of weft, filling warp and binder warp yarns are measured by using computed tomography (CT) technology while the cross-sectional shape of fiber bundles and the orientation of yarns under certain compact effects are fully considered. Regarding the fiber bundle region as porous media, an unit cell model of the 2.5D-woven carbon fabrics is set up, and resin flow process is simulated by Computational Fluid Dynamics ( CFD ) method. The simulation results of the in-plane permeability are proved to be well consistent with the experimental data. Finally, using this method, the in-plane permeability of 2.5D-woven carbon fabrics with different fiber volume fractions (V_f) are predicted, and the changing tendency under different compressive deformation are analysed. (paper)