Non-isothermal '2-D flow/3-D thermal' developments encompassing process modelling of composites: flow/thermal/cure formulations and validations

In the manufacturing process of large geometrically complex components comp rising of fibre-reinforced composite materials by resin transfer molding (R TM), the process involves injection of resin into a mold cavity filled with porous fibre preforms. The overall success of the RTM manufacturing proces s depends on the complete impregnation of the fibre mat by the polymer resi n, prevention of polymer gelation during filling, and subsequent avoidance of dry spots. Since a cold resin is injected into a hot mold, the associate d physics encompasses a moving boundary value problem in conjunction with t he multi-disciplinary study of flow/thermal and cure kinetics inside the mo ld cavity. Although experimental validations are indispensable, routine man ufacture of large complex structural geometries can only be enhanced via co mputational simulations, thus eliminating costly trial runs and helping the designer in the set-up of the manufacturing process. This study describes the computational developments towards formulating an effective simulation- based design methodology using the finite element method. The specific appl ication is for thin shell-like geometries with the thickness being much sma ller than the other dimensions of the part. Due to the highly advective nat ure of the non-isothermal conditions involving thermal and polymerization r eactions, special computational considerations and stabilization techniques are also proposed. Validations and comparisons with experimental results a re presented whenever available. Copyright (C) 2001 John Wiley & Sons, Ltd.