Meso-scale modelling of complex fibre composite geometries using an immersed boundary method

This paper investigates the application of immersed methods to simplify the discretisation and modelling process for meso-scale geometries in fibre-reinforced composites. The geometry of meso-scale structures in fibre-reinforced composites can often be categorised as complex, and frequently presents considerable challenges for meshing software. This complexity necessitates either time-consuming manual intervention or the adoption of simplified discretisation approaches, such as voxel methods, which may compromise accuracy. To address this issue, we study the use of immersed boundary methods, in combination with B-splines, for the discretisation of the matrix regions of the meso-scale geometry. This combination has the potential to minimise the requirement for manual intervention in the discretisation processes with little effect to the accuracy of e.g. stresses. We validate the proposed modelling framework in three numerical examples, where homogenised stiffnesses and stress levels are analysed in various fibre composite architectures. • Finite Cell Method for automatic discretisation of matrix regions in meso-scale fibre composites models. • Ghost penalty method for stabilisation and avoiding artificial stress peaks in results. • Homogenisation of membrane and bending stiffness in 3D woven composite with complex geometry. • Investigation on how transverse stresses in thin-ply woven composites are affected by different bundle thicknesses.