Development Of Multi-Material Overhead Stowage Systems For Commercial Aircrafts By Using New Design and Production Methods 2019-01-1858
The relevance of innovative and functional lightweight components for aircrafts has risen significantly during the recent years. In this context, modern lightweight materials as well as cost-efficient and time-saving manufacturing technologies are required for a future aircraft production.
The so called Hybrid SMC Technology and the SMC-Foam-Sandwich Technology are promising approaches for the cost-efficient and time-saving manufacturing of lightweight, geometrically complex and functional aircraft components. Both technologies have been used for the development of a new generation overhead stowage system. It is realized by sidewalls made out of enhanced SMC technologies with directly implemented metallic load introduction elements and regular sandwich structures that can be assembled by a quick-assembly principle.
Due to the glass fibers in the shape of chopped long fibers with no predominant direction in SMC material, continuous carbon fiber tailored fiber placement (TFP) fabrics were integrated to increase mechanical properties. Because of several load introduction points in the demonstration part, carbon fiber loops are a good and efficient possibility to transfer these loads.
The challenge in the virtual design process of SMC composites is the highly process dependent fiber architecture which leads to a large range of material properties even within a single component. The straight-forward way of simulating SMC composites is to assume a random fiber orientation and thus to use isotropic and homogeneous material properties obtained from testing. However, it is observed that especially in regions with variations in thickness (ribs, load introductions, etc.), the real fiber orientation and distribution may violate these assumptions of isotropy and homogeneity. To assess these deviations, a modelling strategy as well as new computing method is proposed.
Hence, this paper deals with the development of cost-efficient and lightweight multi-material overhead stowage systems realized by new material combinations, production technologies, design approaches, computing methods as well as assembly principles. The overall results of the recent investigations validated by the new design concept for overhead stowage systems are in the focus of this work.
Marc Fette, Holger Büttemeyer, Daniel Krause PhD, Gunnar Fick
Composite Technology Center / CTC GmbH, Faserinstitut Bremen E.V., german aerospace center (dlr), 3D Systems GmbH