Process modeling in resin transfer molding as a method to enhance product quality

Resin transfer molding (RTM) has drawn interest in recent years as an attractive technique for the manufacture of advanced fiber-reinforced composite materials. A major issue in this new manufacturing process is the reduction of voids during the resin fill process so that products with high quality are manufactured. Process modeling is particularly useful in understanding, designing, and optimizing the process conditions. The purpose of this paper is to illustrate the importance of mathematical and numerical modeling to this industrial problem. First, an overview of the RTM process, its manufacturing problems, and related background issues is given. A survey of various RTM models developed in recent years by researchers in this field are then presented. Finally, as an application, a novel two-phase flow model, developed recently by the authors, is proposed to study the formation and migration of the macrovoids, a major manufacturing problem. The unique feature of this model is the identification of local pressure as a major mobilization factor of these macrovoids. It is demonstrated that the model is in good agreement with experimental results.