| The recent interest in the development of small UAVs and micro air vehicles has revealed a need for a more thorough understanding of the aerodynamics of small airplanes flying at low speeds. In response to this need, the present work presents a study of the lift, drag, and pitching moment characteristics of wings of low aspect ratio operating at low Reynolds numbers. Wind tunnel tests of wings with aspect ratios between 0.5 and 2.0, four distinct planforms, thickness-to-chord ratios of ≈2%, and 5-to-1 elliptical leading edges have been conducted as part of this research. The Reynolds numbers considered were in the range of 70,000 to 200,000. Analysis of the data includes comparison of lift-curve slope, induced-drag coefficient, and maximum lift coefficient with theory, discussion of aerodynamic center, and the effects of Reynolds number, camber, and leading-edge shape.; As an example of an application of this wind tunnel data, the experimental results are implemented within an aircraft performance prediction procedure. This procedure is incorporated into a genetic algorithm optimization program that identifies near-optimum MAV configurations given certain requirements and constraints. Results obtained by use of this optimization procedure have revealed that useful design tools can be developed based on the experimental database. |
