AIAA 2002–5402 Complete Configuration Aero-Structural Optimization Using a Coupled Sensitivity Analysis Method

This paper focuses on the demonstration of a new integrated aero-structural design method for aerospace vehicles. The approach combines an aero-structural analysis solver, a coupled aero-structural adjoint solver, a geometry-based analysis and design integration strategy, and an efficient gradient-based optimization algorithm. The aero-structural solver ensures highly accurate solutions by using high-fidelity models for both disciplines as well as a high-fidelity coupling procedure. The Euler equations are solved for the aerodynamics and a detailed finite element model is used for the primary structure. The coupled aero-structural adjoint solution is used to calculate the needed sensitivities of aerodynamic and structural cost functions with respect to both aerodynamic shape and structural variables. The geometric outer mold line (OML) serves not only as an interface between the two disciplines for both the state and costate systems, but also as an interface between the numerical optimization algorithm and the high-fidelity analyses. Another set of design variables parameterizes a structure of fixed topology. Kreisselmeier–Steinhauser functions are used to reduce the number of structural constraints in the problem. Sample results comparing a fully coupled aero-structural design with a more traditional sequential optimization are presented.