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Vacuum assisted resin transfer molding (VARTM) is a liquid composite molding (LCM) technique used to manufacture large scale composite structures. Fiber preforms are placed on a tool surface and covered by a flow enhancement layer and a plastic bag. A vacuum is drawn on the system to infuse the resin. When the resin does not fully saturate the empty regions in between the fibers, voids are created. The fiber tows in woven and stitched preforms have a much lower permeability as compared to the bulk permeability of the fabric. Hence, fiber tows saturate with resin later than the pores between fiber tows and are more prone to voids. This study explores the impact of extended resin bleeding time and additional flow resistance at the vent on the void content within fiber tows both experimentally and by numerical simulation. Samples were machined from each of the manufactured panels and analyzed using …