Practical and theoretic analysis of resin flow in vacuum assisted resin transfer molding processes

In this study, the non-isothermal resin infiltration during the VARTM process has been analyzed and characterized. In particular, the resin flow through the fibers has been described by the Darcy law and introducing the degree of saturation, the percent of void effectively occupied by the resin within a control volume, as variable in order to account for the moving boundary nature of the problem. Some preliminary tests to measure the advancement of a reference substance, pure water, between the reinforcement fibers with embedded optic fibers sensors, show the capability of a new sensorial technology, based on use of non intrusive fiber optic COTS components, assembled into an original way. These sensors will be used for real time monitoring of the resin flow during the experimental infusion tests and for in-situ demonstration of the capability and the reliability of the model, in the aim to assure a "process repeatability". Due the effectiveness lack of repeatability of VARTM, the Authors propose an approach to extract a parameter during the process, meaning a "Deviation" of modelized output (MOD Modelized Output Deviation). This parameter, obtained by use of optic fibers technology, may improve the standard quality of the production, analyzing and correcting with feed-back capability the efficiency of the moulded manufactured devices. © 2005 WILEY-VCH Verlag GmbH & KGaA, Weinheim.