The design of aeronautical components in composite materials with compensation for cure-induced deformations

This thesis aims to develop a software-based method to support manufacturers of composite components in managing cure-induced deformations caused by autoclave cure cycles. The proposed approach addresses the issue by accounting for residual stresses generated during the curing process of composite laminates, enabling the estimation and prediction of final part deformations. Additionally, it allows for compensation by modifying the original tool geometry, thus significantly reducing the development time of new parts, eliminating trial-and-error approaches, and optimizing process cycles. This leads to cost reductions and the achievement of tighter tolerances. The Ansys add-on Ansys Composite Cure Simulation (ACCS) will be employed to achieve these objectives. Initially, 25x25 cm plates made of unidirectional (UD) and woven fabric prepregs will be analyzed. A thorough evaluation of the compensation procedure will be carried out to enhance the accuracy of the final part shape. This assessment will refine the methodology to minimize deviations between the simulated and the actual manufactured components. Finally, the deformation prediction process will be applied to a section of a fuselage skin panel similar to the one used in the Airbus A350 XWB. In combination with Ansys ACCS, other Ansys tools, such as Workbench, SpaceClaim, and Mechanical (including Composite Pre, Transient Thermal, and Static Structural), will be utilized. These simulation environments will streamline the workflow, facilitating 3D modelling, thermal analysis, and static structural analysis to predict deformations and residual stresses. The final results will closely align with real-world production outcomes. Although discrepancies may arise due to parameter approximations, the findings remain highly valuable. Despite these limitations, the results provide a solid foundation for further refinements and process optimizations.