A CAD-Free Approach to High-Fidelity Aerostructural Optimization

Geometry parametrization for high-fidelity multidisciplinary optimization is an impor-tant and complex problem. We present a CAD-free geometry parametrization method using a free-from deformation volume approach. This approach yields several important advantages over other parametrization techniques, the most of important of which is the efficient computation of analytic derivatives for gradient-based optimization. A parallel, hybrid, algebraic-linear-elasticity mesh perturbation scheme which produces high quality perturbed meshes with low computational effort is also presented. We couple an Euler CFD solver with a finite-element model that uses fourth-order degenerate shell elements. As a demonstration problem, we perform the aerostructural redesign of a subsonic wing for transonic flight conditions. We show that this optimization problem captures some of the complex multidisciplinary trade-offs inherent in wing design. I