Hand layup method is normally used for manufacturing composite parts with large and complex geometry where as Resin Transfer Moulding (RTM) process is a better substitute, but is sparingly used due to lack of proper manufacturing technology. Developments of RTM manufacturing process always requires a proper mould design. In addition, difficulty in the tooling design and mould fabrication cost increases with increase in size and complexity of the component. The scale down strategy of full scale product avoids bigger size mould requirements, prototype bulk production for product testing and quality check at the starting phase of product development. Moreover, the mould scale down strategy can be used to validate the process and the product with less capital input. In this work, a methodology to develop a RTM technology for manufacturing a complex and large composite structure utilizing the process simulation were demonstrated using high speed cab front as selected component.
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A review of current approaches in modeling and simulation of the RTM process was presented by Shojaei et al (2003). It had been reported that the mould of shell like geometry having thickness much smaller than the length and width, was often considered to be two-dimensional. Therefore, the resin flow in a three-dimensional thin cavity had been modeled as a two-dimensional problem. Finite element method (FEM) was often preferred by the researchers to mathematically model the resin flow for the ease of application to all kind of geometries and boundary conditions can be modeled easily (Wang and Lee (1989), Fracchia et al. (1989), Bruschke and Advani (1990), Calhoun et al. (1996), Lim and Lee (2000), Phelan (1997)). The commercially available FEM packages such as ANSYS, LUSAS, NASTRAN, ABAQUS etc., cannot directly support RTM process simulation, whereas these can support mould filling simulations using homogenization technique with limitations of heat transfer and cure kinetics analysis. Moreover, these packages do not have separate process simulation module and this led research groups to develop their own codes such as LIMS (Advani (1994), Bruschke and Advani (1994)), LIMS3D (Varma and Advani (1994)), RTMSIM (Lin and Hahn (1996)) etc., to achieve their requirements. To find ever faster routes to RTM process simulation, commercially available specialized software packages such as PAM-RTM, RTM-Work that simulates various isothermal, non-isothermal, injection-compression, vacuum associated and auto clave moulding processes had been launched into the market. There had been a few work published on RTM process simulation for applications such as automobile parts (Verrey et al.(2006), Demaria et al. (2007))) using PAM-RTM software.