Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-08T05:37:53.381Z Has data issue: false hasContentIssue false
  • English
  • Français

Vortex formation on surging aerofoils with application to reverse flow modelling

Published online by Cambridge University Press:  16 November 2018

Philip B. Kirk  and
Anya R. Jones Open the ORCID record for Anya R. Jones [Opens in a new window]
Philip B. Kirk
Affiliation:
Department of Aerospace Engineering, University of Maryland, College Park, MD 20742, USA
Anya R. Jones*
Affiliation:
Department of Aerospace Engineering, University of Maryland, College Park, MD 20742, USA
*
†Email address for correspondence: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

The leading-edge vortex (LEV) is a powerful unsteady flow structure that can result in significant unsteady loads on lifting blades and wings. Using force, surface pressure and flow field measurements, this work represents an experimental campaign to characterize LEV behaviour in sinusoidally surging flows with widely varying amplitudes and frequencies. Additional tests were conducted in reverse flow surge, with kinematics similar to the tangential velocity profile seen by a blade element in recent high-advance-ratio rotor experiments. General results demonstrate the variability of LEV convection properties with reduced frequency, which greatly affected the average lift-to-drag ratio in a cycle. Analysis of surface pressure measurements suggests that LEV convection speed is a function only of the local instantaneous flow velocity. In the rotor-comparison tests, LEVs formed in reverse flow surge were found to convect more quickly than the corresponding reverse flow LEVs that form on a high-advance-ratio rotor, demonstrating that rotary motion has a stabilizing effect on LEVs. The reverse flow surging LEVs were also found to be of comparable strength to those observed on the high-advance-ratio rotor, leading to the conclusion that a surging-wing simplification might provide a suitable basis for low-order models of much more complex three-dimensional flows.

JFM classification

Aerodynamics: Aerodynamics Wakes/Jets: Separated flows Vortex Flows: Vortex Flows
Type
JFM Papers
Information
Journal of Fluid Mechanics , Volume 859 , 25 January 2019 , pp. 59 - 88
Copyright
© 2018 Cambridge University Press 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Akkala, J. M. & Buchholz, J. 2017 Vorticity transport mechanisms governing the development of leading-edge vortices. J. Fluid Mech. 829, 512–537.Google Scholar
Birch, J. & Dickinson, M. 2003 The influence of wing–wake interactions on the production of aerodynamic forces in flapping flight. J. Expl Biol. 206 (13), 2257–2272.Google Scholar
Birch, J. M. & Dickinson, M. H. 2001 Spanwise flow and the attachment of the leading-edge vortex on insect wings. Nature 412 (6848), 729–733.Google Scholar
Buchner, A.-J., Lohry, M. W., Martinelli, L., Soria, J. & Smits, A. J. 2015 Dynamic stall in vertical axis wind turbines: comparing experiments and computations. J. Wind Engng Ind. Aerodyn. 146, 163–171.Google Scholar
Carr, Z. R. & Ringuette, M. J. 2014 Flow structure of low-aspect-ratio rotating wings from dye visualization. AIAA J. 52 (5), 1081–1086.Google Scholar
Chen, K. K., Colonius, T. & Taira, K. 2010 The leading-edge vortex and quasisteady vortex shedding on an accelerating plate. Phys. Fluids 22 (3), 033601.Google Scholar
Choi, J., Colonius, T. & Williams, D. R. 2015 Surging and plunging oscillations of an airfoil at low Reynolds number. J. Fluid Mech. 763, 237–253.Google Scholar
Choudhry, A., Leknys, R., Arjomandi, M. & Kelso, R. 2014 An insight into the dynamic stall lift characteristics. Exp. Therm. Fluid Sci. 58, 188–208.Google Scholar
Dickinson, M., Lehmann, F. O. & Sane, S. 1999 Wing rotation and the aerodynamic basis of insect flight. Science 284 (5422), 1954–1960.Google Scholar
Disotell, K. J., Nikoueeyan, P., Naughton, J. W. & Gregory, J. W. 2016 Global surface pressure measurements of static and dynamic stall on a wind turbine airfoil at low Reynolds number. Exp. Fluids 57 (5), 82.Google Scholar
Dunne, R. & McKeon, B. J. 2015 Dynamic stall on a pitching and surging airfoil. Exp. Fluids 56 (8), 1–15.Google Scholar
Eldredge, J. D. & Jones, A. R. 2019 Leading-edge vortices: mechanics and modeling. Annu. Rev. Fluid Mech. 51, (to appear, doi:10.1146/annurev-fluid-010518-040334).Google Scholar
Ellington, C. 1984 The aerodynamics of hovering insect flight. III. Kinematics. Phil. Trans. R. Soc. Lond. B 78, 41–78.Google Scholar
Eslam Panah, A., Akkala, J. M. & Buchholz, J. 2015 Vorticity transport and the leading-edge vortex of a plunging airfoil. Exp. Fluids 56 (8), 160.Google Scholar
Favier, D., Agnes, A., Barbi, C. & Maresca, C. 1988 Combined translation/pitch motion – a new airfoil dynamic stall simulation. J. Aircraft 25 (9), 805–814.Google Scholar
Ferreira, C. S., van Kuik, G., van Bussel, G. & Scarano, F. 2008 Visualization by PIV of dynamic stall on a vertical axis wind turbine. Exp. Fluids 46 (1), 97–108.Google Scholar
Gardner, A. D., Richter, K., Mai, H., Altmikus, A. R. M., Klein, A. & Rohardt, C. H. 2013 Experimental investigation of dynamic stall performance for the EDI-M109 and EDI-M112 airfoils. J. Am. Helicopter Soc. 58 (1), 1–13.Google Scholar
Garmann, D. J. & Visbal, M. R. 2014 Dynamics of revolving wings for various aspect ratios. J. Fluid Mech. 748, 932–956.Google Scholar
Gharali, K. & Johnson, D. A. 2013 Dynamic stall simulation of a pitching airfoil under unsteady freestream velocity. J. Fluids Struct. 42, 228–244.Google Scholar
Granlund, K., Monnier, B., Ol, M. & Williams, D. R. 2014 Airfoil longitudinal gust response in separated versus attached flows. Phys. Fluids 26 (2), 027103.Google Scholar
Granlund, K. O., Ol, M. V. & Jones, A. R. 2016 Streamwise oscillation of airfoils into reverse flow. AIAA J. 54 (5), 1–9.Google Scholar
Greenberg, J. M.1947 Airfoil in sinusoidal motion in a pulsating stream. NACA Tech. Rep. 1326.Google Scholar
Gursul, I. & Ho, C.-M. 1992 High aerodynamic loads on an airfoil submerged in an unsteady stream. AIAA J. 30 (4), 1117–1119.Google Scholar
Hansen, A. C. & Butterfield, C. P. 1993 Aerodynamics of horizontal-axis wind turbines. Annu. Rev. Fluid Mech. 25, 115–149.Google Scholar
Hodara, J., Lind, A. H., Jones, A. R. & Smith, M. J. 2016 Collaborative investigation of the aerodynamic behavior of airfoils in reverse flow. J. Am. Helicopter Soc. 61, 1–15.Google Scholar
Isaacs, R. 1945 Airfoil theory for flows of variable velocity. J. Aeronaut. Sci. 54 (1), 113–117.Google Scholar
Jardin, T. 2017 Coriolis effect and the attachment of the leading edge vortex. J. Fluid Mech. 820, 312–340.Google Scholar
Kaufmann, K., Merz, C. B. & Gardner, A. D. 2017 Dynamic stall simulations on a pitching finite wing. J. Aircraft 54 (4), 1303–1316.Google Scholar
Leishman, J. G. 2006 Principles of Helicopter Aerodynamics, 2nd edn. Cambridge University Press.Google Scholar
Lind, A. H. & Jones, A. R. 2016 Unsteady aerodynamics of reverse flow dynamic stall on an oscillating blade section. Phys. Fluids 28 (7), 077102.Google Scholar
Lind, A. H., Smith, L. R., Milluzzo, J. I. & Jones, A. R. 2016 Reynolds number effects on rotor blade sections in reverse flow. J. Aircraft 53 (5), 1248–1260.Google Scholar
Lind, A. H., Trollinger, L. N., Manar, F. H., Chopra, I. & Jones, A. R. 2017 Flowfield measurements of reverse flow on a high advance ratio rotor. In 43rd European Rotorcraft Forum, Milan, Italy. Paper no. 699.Google Scholar
Lua, K. B., Lim, T. T. & Yeo, K. S. 2011 Effect of wing–wake interaction on aerodynamic force generation on a 2D flapping wing. Exp. Fluids 51 (1), 177–195.Google Scholar
Manar, F., Mancini, P., Mayo, D. & Jones, A. R. 2016 Comparison of rotating and translating wings: Force production and vortex characteristics. AIAA J. 54 (2), 519–530.Google Scholar
Manar, F. H. & Jones, A. R. 2017 Vorticity production at the leading edge of flat plates at high incidence. In 55th AIAA Aerospace Sciences Meeting, Grapevine, TX, AIAA Paper 2017-0545.Google Scholar
Mancini, P., Manar, F. H., Granlund, K., Ol, M. V. & Jones, A. R. 2015 Unsteady aerodynamic characteristics of a translating rigid wing at low Reynolds number. Phys. Fluids 27 (12), 123102.Google Scholar
Maresca, C., Favier, D. & Rebont, J. 1979 Experiments on an aerofoil at high angle of incidence in longitudinal oscillations. J. Fluid Mech. 92 (4), 671–690.Google Scholar
McCroskey, W. J. 1982 Unsteady airfoils. Annu. Rev. Fluid Mech. 14, 285–311.Google Scholar
Medina, A. & Jones, A. R. 2016 Leading-edge vortex burst on a low-aspect-ratio rotating flat plate. Phys. Rev. Fluids 1 (4), 044501.Google Scholar
Mulleners, K. & Raffel, M. 2012 The onset of dynamic stall revisited. Exp. Fluids 52, 779–793.Google Scholar
Mulleners, K. & Raffel, M. 2013 Dynamic stall development. Exp. Fluids 54 (2), 1469.Google Scholar
Ol, M. V., Bernal, L. P., Kang, C.-K. & Shyy, W. 2009 Shallow and deep dynamic stall for flapping low Reynolds number airfoils. Exp. Fluids 46 (5), 883–901.Google Scholar
Panda, J. & Zaman, K. B. M. Q. 1994 Experimental investigation of the flow field of an oscillating airfoil and estimation of lift from wake surveys. J. Fluid Mech. 265, 65–95.Google Scholar
Pierce, G. A., Kunz, D. L. & Malone, J. B. 1978 The effect of varying freestream velocity on airfoil dynamic stall characteristics. J. Am. Helicopter Soc. 23 (2), 27–33.Google Scholar
Pitt Ford, C. & Babinsky, H. 2013 Lift and the leading-edge vortex. J. Fluid Mech. 720, 280–313.Google Scholar
Shyy, W., Trizila, P., Kang, C.-K. & Aono, H. 2009 Can tip vortices enhance lift of a flapping wing? AIAA J. 47 (2), 289–293.Google Scholar
Srygley, R. B. & Thomas, A. L. R. 2002 Unconventional lift-generating mechanisms in free-flying butterflies. Nature 420 (6916), 660–664.Google Scholar
Taira, K. & Colonius, T. 2009 Three-dimensional flows around low-aspect-ratio flat-plate wings at low Reynolds numbers. J. Fluid Mech. 623, 187–207.Google Scholar
Theodorsen, T.1935 General theory of aerodynamic instability and the mechanism of flutter. NACA Tech. Rep. 496.Google Scholar
Tsai, H.-C. & Colonius, T. 2016 Coriolis effect on dynamic stall in a vertical axis wind turbine. AIAA J. 54 (1), 216–226.Google Scholar
Visbal, M. R. 2011 Numerical investigation of deep dynamic stall of a plunging airfoil. AIAA J. 49 (10), 2152–2170.Google Scholar
Visbal, M. R. & Garmann, D. J. 2018 Analysis of dynamic stall on a pitching airfoil using high-fidelity large-eddy simulations. AIAA J. 56 (1), 46–63.Google Scholar
Wojcik, C. J. & Buchholz, J. 2014 Vorticity transport in the leading-edge vortex on a rotating blade. J. Fluid Mech. 743, 249–261.Google Scholar
Wolfinger, M. & Rockwell, D. 2014 Flow structure on a rotating wing: effect of radius of gyration. J. Fluid Mech. 755, 83–110.Google Scholar
Wu, T. Y. 2011 Fish swimming and bird/insect flight. Annu. Rev. Fluid Mech. 43 (1), 25–58.Google Scholar