The swept wing configuration showed interesting results for the leading edge phenomena in recent studies. The most important outcomes showed that configurations with higher wing loading at the tip (such as tapered and swept wings), tend to be more susceptible to the effect of tubercles, giving an important increase in stall angle, and consequently, in maximum lift coefficient. A remarkable gain of about 20% on C_(Lmax) (without large penalties on drag coefficient) was obtained in 30° swept models with taper ratios of 1 and 0.5.This increase in lift force is associated to the fact that the wavy configurations exhibit a delay on stall progression from wing tip to the root as consequence of the tubercle effects, which maintain the flow attached on leading edge at high angles of attack. To investigate the relationship between the increase in maximum lift coefficient and the swept angle, and continue with the study presented by Abrantes et al.", a series of experiments were conducted on six wing configurations. The range of sweep-angles include wings with 30°, 40° and 50°, as well as two variations of taper ratio (TR=1 and TR=0.5). All models had an underlying NACA 0020 airfoil and a wavy geometry with amplitude A=0.03c and wavelength λ=0.11. The purpose of this research consisted in evaluating the drag and lifts forces at Reynolds number of 200,000 for all seven models and compares their results with the smooth wings. In addition, a flow visualization analysis using oil technics was included in order to better understand the involved phenomena.
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