Force Measurements and Wake Surveys of a Swept Tubercled Wing
Publication: Journal of Aerospace Engineering
Volume 30, Issue 3
Abstract
Force measurements and wake surveys have been conducted on two swept NACA 0021 wings. One wing had a smooth leading edge, while the other wing had a tubercled leading edge. The force measurements and the wake survey results were in good agreement. Between 0 and 8° angles of attack, tubercles reduced the lift coefficient by 4–6%. For the same range of angles of attack, tubercles reduced the drag coefficient by 7–9.5%. Tubercles increased the lift-to-drag ratio of this wing by 2–6%, and increased the maximum lift-to-drag ratio by 3%. At angles of attack higher than 8°, tubercles typically decreased the lift coefficient and the lift-to-drag ratio, while substantially increasing the drag coefficient. The wake surveys revealed that tubercles reduced the drag coefficient near the wingtip and that they also spatially modulated the drag coefficient into local maxima and minima in the spanwise direction. Typically, tubercles reduced the drag coefficient over the peaks where the tubercle vortices produced downwash. Conversely, tubercles increased the drag coefficient over the troughs, where upwash occurred. The majority of the drag coefficient reduction occurred over the tubercled wingspan.
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Acknowledgments
The authors appreciate the assistance of Sophie Dawson, Oliver Durance, Tony Huang, Simon McDonald, and Jeremy Yu. The authors thank Assoc. Prof. Con Doolan and Dr. Zebb Prime for their contributions to this work. Research undertaken for this report has been assisted with a grant from the Sir Ross and Sir Keith Smith Fund (Smith Fund) (www.smithfund.org.au). The support is acknowledged and greatly appreciated.
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Information & Authors
Information
Published In
Journal of Aerospace Engineering
Volume 30 • Issue 3 • May 2017
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Nov 16, 2015
Accepted: Jun 29, 2016
Published online: Sep 1, 2016
Discussion open until: Feb 1, 2017
Published in print: May 1, 2017
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