Injection simulations of thick composite parts manufactured by the RTM process

In order to simulate the resin flow occurring in a reinforcement during manufacture of composite materials by resin transfer moulding (RTM); the numerical codes need data such as the permeability, K, of the reinforcement. In the case of thick parts (e.g. a few centimetres thick), the spatial components of the permeability can be deduced from experimental kinetics if we are able to visualise the resin path in the reinforcement opaque bulk. Here we describe the original technique we used to achieve this aim and we demonstrate the results of X-ray spectrography for the determination of the kinetics of spatial flows through a porous medium. We then propose a mathematical approach in order to treat our experimental results and calculate the values of K. Finally, examples of simulations are compared to the corresponding experimental observations. These simulations are obtained from two numerical codes based on the finite-differences technique with curvilinear meshes and finite elements with control volumes, respectively.