  With more efficient structures, last trends in aeronautics have witnessed an
increased flexibility of wings, calling for adequate design and optimization
approaches. To correctly model the coupled physics, aerostructural optimization
has progressively become more important, being nowadays performed also
considering higher-fidelity discipline methods, i.e., CFD for aerodynamics and
FEM for structures. In this paper a methodology for high-fidelity
gradient-based aerostructural optimization of wings, including aerodynamic and
structural nonlinearities, is presented. The main key feature of the method is
its modularity: each discipline solver, independently employing algorithmic
differentiation for the evaluation of adjoint-based sensitivities, is
interfaced at high-level by means of a wrapper to both solve the aerostructural
primal problem and evaluate exact discrete gradients of the coupled problem.
The implemented capability, ad-hoc created to demonstrate the methodology, and
freely available within the open-source SU2 multiphysics suite, is applied to
perform aerostructural optimization of aeroelastic test cases based on the
ONERA M6 and NASA CRM wings. Single-point optimizations, employing Euler or
RANS flow models, are carried out to find wing optimal outer mold line in terms
of aerodynamic efficiency. Results remark the importance of taking into account
the aerostructural coupling when performing wing shape optimization.
