Dynamic Response of Highly Flexible Flying Wings

This paper presents a method to model and analyze the coupled nonlinear flight dynamics and aeroelasticity of highly flexible flying wings. A low-order nonlinear strain-based finite element framework is used, which is capable of capturing the fundamental impact of geometrically nonlinear effects in a computationally effective formulation target for preliminary vehicle design and control evaluation. A simple model to capture the change in the wing torsional stiffness due to skin wrinkling arising from large bending curvatures is proposed. Finite-state unsteady subsonic aerodynamics with simplified stall models are incorporated to complete the aeroelastic representation of flying wings. In studying the flying wing dynamic response, a spatially and temporally distributed discrete gust model is introduced. With the proposed formulations, numerical studies are conducted based on a representative highly flexible flying wing subjected to finite disturbances.