Formulation of Analytical Design Derivatives for Nonlinear Unsteady Aeroelasticity

The engineering community has devoted considerable recent attention to non-traditional aircraft concepts, where nonlinear, unsteady, coupled aeroelastic physics have been found to drive the design process. There is a lack of current research aimed at bringing these physical concepts into a formal optimization environment, which is the focus of the current work. A numerical framework is developed to capture the unsteady aeroelastic interactions between a nonlinear shell and the surrounding flow. An analytical sensitivity analysis of the model is then discussed, computing the derivative of the aerodynamic force production with respect to a large vector of structural design variables. The work concludes with a series of gradient-based aeroelastic optimization studies, demonstrating the efficacy of analytical gradients towards tailoring the complex interaction between fluid and structure for optimal performance. I. Introduction