Reynolds Number Effects on Thrust Coefficients and PIV for Flapping Wing Micro Air Vehicles.

摘要

For the last several years the Air Force Institute of Technology (AFIT) has conducted research in aerodynamics for flapping wing micro air vehicles (MAVs). The focus of this research was to augment this effort by measuring thrust, velocity, and torque in tanks of water and glycerin using a scale and a reaction torque cell. The results for different flapping mechanisms are compared to a rotating propeller with the goal of elucidating the design trade space between rotorcraft and flapping wings at Reynolds numbers less than 100,000. In addition, flow visualization and quantitative velocity data were captured in the wake of the flapping wing. One flapping-wing mechanism was designed to incorporate a coupled 4-bar planar and 4-bar spatial linkage system to prescribe motion which included both flapping and rotation. Thrust and velocity data were found to follow the general trends for a flapping wing with passive rotation. The passive rotation angle setting was found to alter thrust and velocity patterns.