Modelling flow and filtration in liquid composite moulding of nanoparticle loaded thermosets

This paper presents analytical and numerical models of liquid moulding of hybrid composites. An 1-D analytical solution of Darcy's problem, accompanied by nanoparticle filtration kinetics and conservation, has been developed. A non-linear finite difference model incorporating variations in permeability, porosity and viscosity as a function of local nanoparticle loading was formulated. Comparison of the two models allowed verification of their validity, whilst a mesh sensitivity study demonstrated the convergence of the numerical scheme. The limits of validity of the analytical solution were established over a range of infiltration lengths and filtration rates for different nanoparticle loadings. The analytical model provides an accurate and efficient approximation of through thickness infusion of hybrid composites, whereas use of the numerical scheme is necessary for accurate simulation of in-plane filling processes. The models developed here can serve as the basis of process design/optimisation for the production of hybrid composites with controlled distribution of nano-reinforcement.