ANISOTROPIC PERMEABILITY OF FIBER PREFORMS - CONSTANT FLOW-RATE MEASUREMENT

Fiber preform permeability has a strong influence on the resin impregnation 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 experimental 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 parameters obtained from two linear plots. Experimental data for a commercial fabric confirms the applicability of the procedure. The required equipment setup and the analytical procedure 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.