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.
Get full access to this article
View all available purchase options and get full access to this article.
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.
References
Barlow, J. B., Rae, Jr. W. H., and Pope, A. (1999). Low-speed wind tunnel testing, 3rd Ed., Wiley, New York.
Bolzon, M. D., Kelso, R. M., and Arjomandi, M. (2014) “The effects of tubercles on swept wing performance at Low Angles of attack.” Proc., 19th Australasian Fluid Mechanics Society.
Bolzon, M. D., Kelso, R. M., and Arjomandi, M. (2015). “A review of tubercles and their applications.” J. Aerosp. Eng., .
Bolzon, M. D., Kelso, R. M., and Arjomandi, M. (2016). “Parametric study of the effects of a tubercle’s geometry on wing performance through the use of the lifting-line theory.” Proc., 54th AIAA Aerospace Science Meeting, American Institute of Aeronautics and Astronautics, Reston, VA.
Bradley, G. (2009). “Shark fin wings give airline chiefs something to smile about.” The New Zealand Herald, Auckland, New Zealand.
Brown, F. (1997). “Test could cut aircraft fuel costs.” Aerospace Technology Innovation, Washington, DC.
Brune, G. W. (1994). “Quantitative low-speed wake surveys.” J. Aircraft, 31(2), 249–255.
Custodio, D., Henoch, W., and Johari, H. (2015). “Aerodynamic characteristics of finite span wings with leading-edge protuberances.” AIAA J., 53(7), 1878–1893.
Dieck, R. H. (1992). Measurement uncertainty: Methods and applications, Instrument Society of America, NC.
Fish, F. M., and Battle, J. M. (1995). “Hydrodynamic design of the humpback whale flipper.” J. Morphol., 225(1), 51–60.
Hansen, K. L. (2012). “Effect of leading edge tubercles on airfoil performance.” Ph.D. dissertation, Univ. of Adelaide, Adelaide, Australia.
Hansen, K. L., Kelso, R. M., and Dally, B. B. (2011). “Performance variations of leading-edge tubercles for distinct airfoil profiles.” AIAA J., 49(1), 185–194.
Hansen, K. L., Rostamzadeh, N., Kelso, R. M., and Dally, B. B. (2016). “Evolution of the streamwise vortices generated between leading edge tubercles.” J. Fluid Mech., 788, 730–766.
Harper, C. W., and Maki, R. L. (1964). “A review of the stall characteristics of swept wings.”, NASA, Washington, DC.
Holman, J. P. (1994). Experimental methods for engineers, 6th Ed., McGraw-Hill, New York.
Johari, H., Henoch, C., Custodio, D., and Levshin, A. (2007). “Effects of leading-edge protuberances on airfoil performance.” AIAA J., 49(1), 185–194.
Jurasz, C. M., and Jurasz, V. P. (1979). “Feeding modes of the humpback whale, Megaptera novaeangliae, in southeast Alaska.” Whales Research Institute, Tokyo.
Luckring, J. M. (2010). “A survey of factors affecting blunt leading-edge separation for swept and semi-slender wings.” Proc., AIAA 28th Applied Aerodynamics Conf., American Institute of Aeronautics and Astronautics, Reston, VA.
Miklosovic, D. S., Murray, M. M., and Howle, L. E. (2007). “Experimental evaluation of sinusoidal leading edges.” J. Aircraft, 44(4), 1404–1408.
Miklosovic, D. S., Murray, M. M., Howle, L. E., and Fish, F. E. (2004). “Leading-edge tubercles delay stall on humpback whale (Megaptera novaeangliae) flippers.” Phys. Fluids, 16(5), L39–L42.
Murray, M. M., Miklosovic, D. S., Fish, F., and Howle, L. (2005). “Effects of leading edge tubercles on a representative whale flipper model at various sweep angles.” Proc., Unmanned Untethered Submersible Technology (UUST), Autonomous Undersea Systems Institute, Lee, NH.
Pedro, H. T., and Kobayashi, M. H. (2008). “Numerical study of stall delay on humpback whale flippers.” AIAA Aerospace Sciences Meeting and Exhibit, American Institute of Aeronautics and Astronautics, Reston, VA, 1–8.
Porteous, R., Moreau, D. J, and Doolan, C. J. (2014). “A review of flow-induced noise from finite wall-mounted cylinders.” J. Fluids Struct., 51, 240–254.
Rostamy, N., Sumner, D., Bergstrom, D. J., and Bugg, J. D. (2013). “Instantaneous flow field above the free end of finite-height cylinders and prisms.” Int. J. Heat Fluid Flow, 43, 120–128.
Rostamzadeh, N., Hansen, K. L., Kelso, R. M., and Dally, B. B. (2014). “The formation mechanism and impact of streamwise vortices on NACA 0021 airfoil’s performance with undulating leading edge modification.” Phys. Fluids, 26(10), .
Seshagiri, A., Cooper, E., and Traub, L. W. (2009). “Effects of vortex generators on an airfoil at low Reynolds numbers.” J. Aircraft, 46(1), 116–122.
Shepherd, I. C. (1981). “A four hole pressure probe for fluid flow measurements in three dimensions.” J. Fluids Eng., 103(4), 590–594.
Stein, B., and Murray, M. M. (2005). “Stall mechanism analysis of humpback whale flipper models.” Proc., Untethered Submersible Technology (UUST), Autonomous Undersea Systems Institute, Lee, NH.
TFI (Turbulent Flow Instrumentation). (2011). “Getting started series 100 Cobra probe.” VIC, Australia.
Watts, P., and Fish, F. E. (2001). “The influence of passive, leading edge tubercles on wing performance.” Proc., Unmanned Untethered Submersible Technology (UUST), Autonomous Undersea Systems Institute, NH.
Wei, Z., New, T. H., and Cui, Y. D. (2015). “An experimental study on flow separation control of hydrofoils with leading-edge tubercles at low Reynolds number.” Ocean Eng., 108, 336–349.
Information & Authors
Information
Published In
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
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.