Representative volume element of anisotropic unidirectional carbon–epoxy composite with high-fibre volume fraction

The knowledge of thermal properties of orthotropic layered composite materials is very important in the aeronautics industry. They can be measured with a dedicated apparatus but numerical computations develop strongly. It is well known that the microstructure has a strong impact on the calculation of the effective properties of these heterogeneous materials. The representative volume element (RVE) is then a crucial input to predict reliable results. In composites, fibre distribution often exhibits fibre-rich and fibre-poor regions. In this contribution, we first investigated a quantitative characterization of the microstructure using optical images and spatial descriptors. They give rise to microstructural features but also anisotropy. In a second time, we defined the RVEs of this microstructure for statistical parameters and effective thermal conductivities.