Topology and fibre orientation simultaneous optimisation: A design methodology for fibre-reinforced composite components

Additive manufacturing for fibre-reinforced composite structures is rapidly diffusing, since it enables the production of lightweight structural parts characterized by complex geometries and tailored fibre orientations. Therefore, the development of design methodologies capable to simultaneously optimize the shape of the fibre-reinforced composite part and the fibre orientation in the additive manufacturing process is, at present, of utmost interest among industries and research centres. In this paper, a novel simultaneous optimisation method capable to optimise the topology and the local fibre orientation is proposed. The method is computationally cheap, fast convergent and permits to avoid stress peaks, working efficiently on 2D and on 3D models. The analytical formulation of the problem and the optimisation algorithm are at first described. The optimisation criteria are based on the uniform strain energy density distribution and the fibre alignement along the principal stress direction. The proposed method is then verified with several benchmarks from the literature and with a 3D illustrative example, confirming that it can be effectively and efficiently employed for the optimisation of composite components to be produced through additive manufacturing.