Abstract

Flapping flight shows promise for micro air vehicle design because flapping wings provide superior aerodynamic performance than that of fixed wings and rotors at low Reynolds numbers. In these flight regimes, unsteady effects become increasingly important. This thesis explores some of the unsteady effects that provide additional lift to flapping wings through an experiment-based optimization of the kinematics of a flapping wing mechanism in a water tunnel. The mechanism wings and flow environment were scaled to simulate the flight of the hawkmoth (Manduca sexta) at hovering or near-hovering speeds. The optimization was repeated using rigid and flexible wings to evaluate the impact that wing flexibility has on aerodynamic performance of flapping wings. The trajectories that produced the highest lift were compared using particle image velocimetry to characterize the flow features produced during the periods of peak lift. A leading edge vortex was observed with all of the flapping trajectories and both wing types, the strength of which corresponded to the measured amount of lift of the wing. This research furthers our understanding of the lift-generating mechanisms used in nature and can be applied to improve the design of micro air vehicles.

Degree

College and Department

Ira A. Fulton College of Engineering and Technology; Mechanical Engineering

Rights

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