Shape, Structure, and Kinematic Parameterization of a Power-Optimal Hovering Wing

Abstract

In this paper, we investigate the aeroelastic hovering motions of a highly-flexible flapping wing. It is desired to parameterize the wing shape, structural composition, and kinematic hovering motions, and then minimize the peak power required during the stroke, subject to trim and mechanical failure constraints. The aeroelastic model couples a nonlinear threedimensional beam model to a quasi-steady blade element aerodynamic model, which is then solved in an implicit time-marching manner (with sub-iterations within each time step to accommodate various nonlinearities) until the response becomes time-periodic. Gradients of the response with respect to the disparate design variables are computed analytically for optimization. Power-optimal flapping configurations are found to exploit interdependencies among the three types of design variables to effectively tailor the aeroelastic response.