Anisotropic Permeability of Fiber Preforms: Constant Flow Rate Measurement

Abstract

Fiber preform permeability has a strong influence on the resin impregna tion behavior during polymer composites fabrication. A straightforward procedure has been developed for determining the general anisotropic in-plane permeability character of fiber preforms from constant flow rate mold filling experiments. The procedure is based on the application of Darcy's law to a two-dimensional in-plane flow situation. From ex perimental data on changes in flow front position and inlet pressure with mold filling time, the components of the in-plane permeability tensor can be calculated directly using param eters obtained from two linear plots. Experimental data for a commercial fabric confirms the applicability of the procedure. The required equipment setup and the analytical proce dure are both uncomplicated in nature. The proposed method provides a simple solution to the measurement of permeability and comparison of different preforms for polymer composites application.