Flapping flight is a subject of interest for more than two decades.During this time it has been found that a stable leading edge vortex isresponsible for the high lift coefficient that flapping and revolving wingscan produce. However, many of these studies were limited to Reynoldsnumbers of few hundred, which characterize insects. Recently, the intereston designing and realizing miniature hovering vehicles requires expandingour understanding of the basic flow mechanism which govern such wingmaneuvers at higher Reynolds numbers. In this study the flow field over anaccelerating rotating wing model is analyzed in various Reynolds numbersusing particle image velocimetry. The study depicts the characteristic sizeand time scales of the leading edge vortex up to Reynolds number 2000. Itis shown that LEV circulation capacity increases with Reynolds number;nevertheless, in order to obtain higher LEV circulation (which is relateddirectly to the wing’s lift) the wing acceleration profile should beprescribed accordingly.
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