9522801 Pitchumani Liquid molding with processes like resin transfer molding, is a way to fabricate relatively high volumes of complex, high performance composite products at reasonable costs. A key to the success of liquid molding is uniform and complete filling of a closed and vented mold with resin. Because the inside of the mold is a labyrinth of composite preforms and inserts, the flow permeability is difficult to model and predict. This project uses an analytical and experimental investigation of fractals as a way to describe pore structure. This allows calculation of the permeability inside the mold. With fratal models for the tortuous length and capillary size, the permeability can be determined using Darcy's law so the flow in the closed mold can be calculated using existing numerical codes. An experimental setup to verify this approach uses a three-part Plexiglas mold, and a video and image processing system to document the flow pattern and determine the fractal dimensions of the composite mat. Passing a current through conductive fibers that are part of the preform is a process innovation that will be investigated to improve the uniformity of curing. The impact of this research will be improvements in the design of venting systems and uniform filling in liquid composite molding processes, leading to lower costs and more opportunities for use of these high performance materials. ***
