Ottimizzazione strutturale di una bulkhead di fusoliera di velivoli da trasporto commerciale

The present state-of-the-art of the rear pressure bulkhead foresees the use of two types of materials: aluminium alloy Al2024 (exploited in the applications where tensile or fatigue loads are predominant like in the fuselage paneling) and composite materials (carbon fiber reinforced polymer). For the metallic case, the problem of the deep drawing of an aluminium alloy sheet into a hemispheric dome consists in the phenomenon of wrinkles formation (wrinkling); this is linked to the thickness of the plate and its dimensions. In this thesis we provide a carrying out solution by additive manufacturing. On the base of what developed by Airbus, which created AM spoiler prototypes taking inspiration from the structure of lily pad, this thesis work aims to develop a bulkhead and its stiffeners design optimization. The use of additive manufacturing in the bulkhead production shows two big advantages compared to traditional working: the chance to create complex geometries and the absence of internal residual stress and wrinkling phenomenon. The analysis of the studied structures allows to verify advantage of the rounded bulkhead configuration instead of the plane one (almost one lower order of magnitude for displacements), structural optimization due to stiffeners, consistency with lily pad shape.