کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1718500 | 1013847 | 2012 | 7 صفحه PDF | دانلود رایگان |
The planform, profile, and cross-sectional views of the wing-tip region of a half-wing model with an aspect ratio of 3.2 and three different wing configurations, namely, square-cut, simple fairing, and Whitcombʼs full winglet wing-tip, were visualized at various angles of attack using smoke-wire visualization technique. Visualization pictures clearly show that the wing-tip vortices at different angles of attack and wing-tip configurations had distinct formation and structure characteristics. A comparison of simple fairing and Whitcombʼs winglet configurations shows that the wing-tip vortices of the Whitcombʼs winglet configuration were reduced in strength and displaced outboard and upward, at least in the near-wake region. This resulted in an increased lift-to-drag ratio for the Whitcombʼs winglet configuration. The changes in the wing-tip vortex characteristics and the improved aerodynamic performance of the winglet were confirmed by Particle Image Velocimetry (PIV) measurements of the cross-flow velocity of the wing-tip trailing regions and the force measurement of the model.
Journal: Aerospace Science and Technology - Volume 16, Issue 1, January–February 2012, Pages 40–46