Effect of Plain, Concave and Convex Winglet Geometry on Wing Performance at Various Cant Angles

Abstract

The wingletslocated at aircraft wing ends are used to increase the aerodynamic performanceand reduce fuel consumption by regulating negatively affecting the performanceat the wings end. Therefore, aircraft wings have a critical importance onaerodynamic efficiency. The most efficient winglet model should be used in eachof the flight positions. This study is aimed to investigate the effects ofconcave, convex, and plain winglet geometry on wing performance. The effects ofplain, concave and convex winglet models with cant angles of 30, 45, and 60°were experimentally investigated at the angles of attack ranging from 0 to 20°.The aerodynamic lift and drag coefficients generated by each design weremeasured in wind tunnel tests conducted at a Reynolds number of 2.5×105,and the effect of the winglet's shape on wing performance was compared. Thedata obtained reveal that various wingtip designs have significant effects onthe aerodynamic properties of the wing. At low, moderate and high angles of attack, thehighest lift is achieved with the 30° cant anglewinglet. The best results for all winglet models in termsof the aerodynamic quality were obtained in the plain winglet model.Furthermore, the aerodynamic quality generally increases with decrease in thecant angles. It is anticipatedthat these findings, obtained from winglet models with various geometricdesigns, could contribute to the development of more efficient winglet geometry.</p