Experimental Investigation into the Aerodynamic Performance of Both Rigid and Flexible Wing Structured Micro-Air-Vehicles

摘要

The Air Force Research Lab, Munitions Directorate, Eglin Air Force Base, Florida has designed a man-portable carbon-fiber Micro-Air-Vehicle (MA V) used for on-the-spot surveillance by Special Operations Forces (SOF) for enemy reconnaissance as well as post-strike Battle Damage Assessment (BDA).The main goals of this experiment are: (1) characterize the flow quality of the new AFIT 3' x 3' wind tunnel and (2) determine the aerodynamic performance characteristics of the 24' span, 6' chord flexible and rigid wing MA V s. The turbulent intensity of the wind tunnel was approximately 2%. Both MA Vs had an average lift slope within 3.5% of the theoretical value. Flexible wings deformed in response to perturbations in local flow field conditions, promulgating the delay of wing stall by nearly double. Aeroelastic effects begin to dominate low speed, laminar Reynolds number effects at tunnel velocities greater than 30 miles per hour. The flexible wing MA V displayed static stability in all three principal control axes (Pitch, Roll, Yaw), while the rigid MA V was not definitively stable in any axis. All flexible wing control surface configurations resulted in predictable and consistent performance between -10 and + 10 elevon deflection. Reponses declined steadily after :+ or -10 showing dramatic direction changes.