THE USE OF FLOW SIMULATIONS OF LARGE COMPLEX COMPOSITE COMPONENTS USING THE VARTM PROCESS

SUMMARY: The Vacuum Assisted Resin Transfer Molding process has gained popularity due to the affordable parts that have been made, now approaching complexity and quality found in traditional aerospace processes. However, the progression of the resin through the mold is complex and was historically not well understood. Therefore, traditionally a trial and error approach was used based on a foundation of tribal knowledge to produce composite parts of good quality. For this reason, during the past decade, significant academic research has been applied to advance processing techniques for composite materials manufacturing. One main research thrust has been the simulation of the resin progression through the fibrous preform. This approach enables understanding of how the resin flows through the mold, and reduces the trial and error approach to infusion design. This tool enables to optimize the processing parameters, as well as weight the benefit of alternative approaches. In this study, a flow simulation tool is used to facilitate the design of the infusion strategy. The effect of the location of the infusion runner channels is explored, with optimal location and pathways proposed. Further, the timing of resin arrival into the various ports of the mold is studied. In order to add repeatability to the process and reduce the chance for error, robustness was used as one of the criteria in selection of the infusion strategy in contrast to the standard approach of resin bleeding and recycling. All of these studies culminate in ensuring a robust infusion approach, both minimizing scrap and maximizing processing efficiency. This will further the aim of manufacturing composite parts with the VARTM process with properties equivalent to autoclave quality.