The design of a coated composite corrugated skin for the camber morphing airfoil

One of the critical components of a morphing wing is the anisotropic skin, which has to be stiff to withstand the aerodynamic loads and flexible to enable the morphing deformations. This work presents the design of an elastomer coated composite corrugated skin for the camber morphing airfoil. The good in-plane strain capability and highly anisotropic behaviour of composite corrugated panels make them very effective in morphing wing applications. The behaviour of these corrugated skins must be investigated comprehensively and optimized in terms of aero-elastic effects and the boundary conditions arising from the internal wing structure. In this article, the geometric parameters of the coated composite corrugated panels are optimized to minimize the in-plane stiffness and the weight of the skin and to maximize the flexural out-of-plane stiffness of the corrugated skin. A finite element code for thin beam elements is used with the aggregate Newton's method to optimize the geometric parameters of the coated corrugated panel. The advantages of the corrugated skin over the elastomer skin for the camber morphing structure are discussed. Moreover, a finite element simulation of the internal structure with the corrugated skin is performed under typical aerodynamic and structural loadings to check the design approach.