Modelling of moisture diffusion in multilayer woven fabric composites

Advanced woven fibre reinforced composites have wide applications in industries. However, the mechanical performance of this kind of composites is significantly affected by the moisture absorption of the polymer matrix. This paper presents a numerical investigation on the moisture diffusion taking place in multilayer woven fabric composites. The transient diffusion process of moisture is examined based on the repeating Representative Unit Cell (RUC) of woven fabrics. Using finite element analysis methods, the microscopic heterogeneity of RUC is described in terms of the tow size, tow cross-section shape and tow weaving configuration of fabrics. The model is then applied to simulate the moisture diffusion within the composites of varied number of plies. Finally, by using a data fitting function for the modelling results, a simple predicting model for moisture saturation time with the increase of the number of plies is proposed for the purpose of practical applications.