A simplified flow model for resin transfer molding of polymer composites

Resin transfer molding (RTM) is an important manufacturing process that holds great potential for low cost and fast processing of large and complicated polymer composite parts and structures. The RTM process involves the impregnation of the reactive polymer resin into preplaced fibrous reinforcements in a mold. Prediction of the flow front locations and filling pattern during the mold filling stage is helpful in identifying the potential problems in the very early stage of a mold design. A model can provide the information for a designer to optimize the process parameters, such as pressure, flow rate, gate locations, and temperature, before the mold is actually built. However, the existing flow models for RTM are quite complicated and require much computational time to accomplish a complete filling simulation, which makes the optimization work very time consuming. In this study, a simplified flow model, which assumes equal pressure near the flow front, is developed to greatly reduce the computational efforts in the flow simulation. Heat transfer and chemical reaction are estimated using simplified Lagrange equations. (Author)