Materials Selection for Aircraft Skin Panels by Integrating Multiple Constraints Design with Computational Evaluations

Abstract

Among the principal load-carrying parts of an aircraft, the center wing box yields the main mechanical load-carrying area and is composed of many structural components and elements such as upper and lower skin panels, internal rods, ribs, stringers, front and rear spars. For the structural analysis of such real complex systems, simplified representations of the same sections would be used alternatively to determine whether components could withstand loadings without experiencing failure, thus stay in the margin of safety. Nevertheless, these components should contribute to weight efficiency while carrying in-plane loads and distribute out-of-plane loads to in-plane members safely. Materials selection plays a crucial role for the determination of such candidate materials along with their material properties in specific structural applications. It is usually performed by considering proper objectives, constraints and free variables with respect to functions of the components of a system. Since Composite Material Handbook (CMH-17), Metallic Materials Properties Development and Standardization (MMPDS), and Preliminary Material Properties Handbook (PMP-HDBK) databases are embedded in the materials selection software (CES Edupack), best candidate materials would be easily identified by using coupling constant(s) such as in multiple-constraints designs. In this study, Ashby’s methodology was applied to determine best candidate materials for constructing skin panels by considering them as bending plates. According to materials selection approach, continuous fiber reinforced epoxy composites was stipulated as one of the best candidate materials. Computational failure analysis was then carried out by referring the proper material properties from the materials selection software.