Thermoplastic composites: glass fibre bundle impregnation modelling

Last years, there has been a trend towards the use of thermoplastic composites, both for mechanical (better fatigue and impact strength), and ease of processing considerations. A major advantage of thermoplastic composites is the ability to continuous processing, other than vacuum bagging and autoclave techniques used on thermosets. Yet, high melt viscosity of termoplastic polymers compared to thermoset resins, requires a thoughtful approach to obtain a proper fibre impregnation quality and consequently good mechanical characteristics. Rather than using Darcy's law for impregnation estimation, a new approach was chosen. It consists of making a Computational Fluid Dynamics (CFD) model of the impregnation process, which allows to predict the optimal process parameters and impregnation quality accurately, given the input parameters pressure gradient during impregnation and the polymer’s viscosity