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Coexistence of dual wing–wake interaction mechanisms during the rapid rotation of flapping wings

Published online by Cambridge University Press:  16 May 2024

Long Chen Open the ORCID record for Long Chen [Opens in a new window]  and
Jianghao Wu Open the ORCID record for Jianghao Wu [Opens in a new window]
Long Chen
Affiliation:
School of Transportation Science and Engineering, Beihang University, Beijing 100191, PR China School of Aeronautic Science and Engineering, Beihang University, Beijing 100191, PR China
Jianghao Wu*
Affiliation:
School of Transportation Science and Engineering, Beihang University, Beijing 100191, PR China
*
†Email address for correspondence: buaawjh@buaa.edu.cn
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Abstract

Insects flip their wings around each stroke reversal and may enhance lift in the early stage of a half-stroke. The possible lift-enhancing mechanism of this rapid wing rotation and its strong connection with wake vortices are still underexplored, especially when unsteady leading-edge vortex (LEV) behaviours occur. Here, we numerically studied the lift generation and underlying vorticity dynamics during the rapid rotation of a low aspect ratio flapping wing at a Reynolds number (${\textit {Re}}$) of 1500. Our findings prove that when the outboard LEV breaks down, an advanced rotation can still enhance the lift in the early stage of a half-stroke, which originates from an interaction with the breakdown vortex in the outboard region. This interaction, named the breakdown-vortex jet mechanism, results in a jet and thus a higher pressure on the upwind surface, including a stronger wingtip suction force on the leeward surface. Although the stable LEV within the mid-span retains its growth and location during an advanced rotation, it can be detrimental to lift enhancement as it moves underneath the wing. Therefore, for a flapping wing at ${\textit {Re}}\sim 10^3$, the interactions with stable and breakdown leading-edge vortices lead to the single-vortex suction and breakdown-vortex jet mechanisms, respectively. In other words, the contribution of wing–wake interaction depends on the spanwise location. The current work also implies the importance of wing kinematics to this wing–wake interaction in flapping wings, and provides an alternative perspective for understanding this complex flow phenomenon at ${\textit {Re}}\sim 10^3$.

JFM classification

Biological Fluid Dynamics: Swimming/flying Vortex Flows: Vortex dynamics
Type
JFM Papers
Information
Journal of Fluid Mechanics , Volume 987 , 25 May 2024 , A16
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Copyright
© The Author(s), 2024. Published by Cambridge University Press

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References

Aono, H., Liang, F. & Liu, H. 2008 Near- and far-field aerodynamics in insect hovering flight: an integrated computational study. J. Expl Biol. 211 (2), 239–257.CrossRefGoogle ScholarPubMed
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.CrossRefGoogle ScholarPubMed
Birch, J.M. & Dickinson, M.H. 2003 The influence of wing–wake interactions on the production of aerodynamic forces in flapping flight. J. Expl Biol. 206 (13), 2257–2272.CrossRefGoogle ScholarPubMed
Cai, X., Kolomenskiy, D., Nakata, T. & Liu, H. 2021 A CFD data-driven aerodynamic model for fast and precise prediction of flapping aerodynamics in various flight velocities. J. Fluid Mech. 915, A114.CrossRefGoogle Scholar
Chen, L., Wang, L., Zhou, C., Wu, J. & Cheng, B. 2022 a Effects of Reynolds number on leading-edge vortex formation dynamics and stability in revolving wings. J. Fluid Mech. 931, A13.CrossRefGoogle Scholar
Chen, L., Wu, J. & Cheng, B. 2019 Volumetric measurement and vorticity dynamics of leading-edge vortex formation on a revolving wing. Exp. Fluids 60, 1–15.CrossRefGoogle Scholar
Chen, L., Wu, J. & Cheng, B. 2020 Leading-edge vortex formation and transient lift generation on a revolving wing at low Reynolds number. Aerosp. Sci. Technol. 97, 105589.CrossRefGoogle Scholar
Chen, L., Wu, J., Zhou, C., Hsu, S.-J. & Cheng, B. 2018 Unsteady aerodynamics of a pitching-flapping-perturbed revolving wing at low Reynolds number. Phys. Fluids 30 (5), 051903.CrossRefGoogle Scholar
Chen, L., Zhang, Y., Zhou, C. & Wu, J. 2023 a Vorticity dynamics of fully developed leading-edge vortices on revolving wings undergoing pitch-up maneuvers. Phys. Fluids 35 (3), 031904.Google Scholar
Chen, L., Zhou, C., Werner, N.H., Cheng, B. & Wu, J. 2023 b Dual-stage radial–tangential vortex tilting reverses radial vorticity and contributes to leading-edge vortex stability on revolving wings. J. Fluid Mech. 963, A29.CrossRefGoogle Scholar
Chen, Z., Li, X. & Chen, L. 2022 b Enhanced performance of tandem plunging airfoils with an asymmetric pitching motion. Phys. Fluids 34 (1), 011910.Google Scholar
Cheng, B., Sane, S.P., Barbera, G., Troolin, D.R., Strand, T. & Deng, X. 2013 Three-dimensional flow visualization and vorticity dynamics in revolving wings. Exp. Fluids 54, 1–12.CrossRefGoogle Scholar
Cheng, X. & Sun, M. 2019 Revisiting the clap-and-fling mechanism in small wasp Encarsia formosa using quantitative measurements of the wing motion. Phys. Fluids 31 (10), 101903.CrossRefGoogle Scholar
Chin, D.D. & Lentink, D. 2016 Flapping wing aerodynamics: from insects to vertebrates. J. Expl Biol. 219 (7), 920–932.CrossRefGoogle ScholarPubMed
Dash, S.M., Lua, K.B., Lim, T.T. & Yeo, K.S. 2018 Enhanced thrust performance of a two dimensional elliptic airfoil at high flapping frequency in a forward flight. J. Fluids Struct. 76, 37–59.CrossRefGoogle Scholar
Dickinson, M.H. 1994 The effects of wing rotation on unsteady aerodynamic performance at low Reynolds numbers. J. Expl Biol. 192 (1), 179–206.CrossRefGoogle ScholarPubMed
Dickinson, M.H., Lehmann, F.-O. & Sane, S.P. 1999 Wing rotation and the aerodynamic basis of insect flight. Science 284 (5422), 1954–1960.CrossRefGoogle ScholarPubMed
Ellington, C.P. 1984 The aerodynamics of hovering insect flight. III. Kinematics. Phil. Trans. R. Soc. Lond. B 305 (1122), 41–78.Google Scholar
Ellington, C.P., Van Den Berg, C., Willmott, A.P. & Thomas, A.L.R. 1996 Leading-edge vortices in insect flight. Nature 384 (6610), 626–630.CrossRefGoogle Scholar
Garmann, D.J., Visbal, M.R. & Orkwis, P.D. 2013 Three-dimensional flow structure and aerodynamic loading on a revolving wing. Phys. Fluids 25 (3), 034101.CrossRefGoogle Scholar
Jardin, T. 2017 Coriolis effect and the attachment of the leading edge vortex. J. Fluid Mech. 820, 312–340.CrossRefGoogle Scholar
Jardin, T. & David, L. 2014 Spanwise gradients in flow speed help stabilize leading-edge vortices on revolving wings. Phys. Rev. E 90 (1), 013011.CrossRefGoogle ScholarPubMed
Jeong, J. & Hussain, F. 1995 On the identification of a vortex. J. Fluid Mech. 285, 69–94.CrossRefGoogle Scholar
Kim, D. & Choi, H. 2007 Two-dimensional mechanism of hovering flight by single flapping wing. J. Mech. Sci. Technol. 21, 207–221.CrossRefGoogle Scholar
Kweon, J. & Choi, H. 2010 Sectional lift coefficient of a flapping wing in hovering motion. Phys. Fluids 22 (7), 071703.CrossRefGoogle Scholar
Lee, Y.J. & Lua, K.B. 2018 Wing–wake interaction: comparison of 2D and 3D flapping wings in hover flight. Bioinspir. Biomim. 13 (6), 066003.CrossRefGoogle ScholarPubMed
Lehmann, F.-O. 2008 When wings touch wakes: understanding locomotor force control by wake–wing interference in insect wings. J. Expl Biol. 211 (2), 224–233.CrossRefGoogle ScholarPubMed
Lentink, D. & Dickinson, M.H. 2009 Rotational accelerations stabilize leading edge vortices on revolving fly wings. J. Expl Biol. 212 (16), 2705–2719.CrossRefGoogle ScholarPubMed
Li, H. & Nabawy, M.R.A. 2022 Capturing wake capture: a 2D numerical investigation into wing–wake interaction aerodynamics. Bioinspir. Biomim. 17 (6), 066015.CrossRefGoogle ScholarPubMed
Lim, T.T., Teo, C.J., Lua, K.B. & Yeo, K.S. 2009 On the prolong attachment of leading edge vortex on a flapping wing. Mod. Phys. Lett. B 23 (3), 357–360.CrossRefGoogle Scholar
Lua, K.B., Lee, Y.J., Lim, T.T. & Yeo, K.S. 2016 a Aerodynamic effects of elevating motion on hovering rigid hawkmothlike wings. AIAA J. 54 (8), 2247–2264.CrossRefGoogle Scholar
Lua, K.B., Lee, Y.J., Lim, T.T. & Yeo, K.S. 2017 Wing–wake interaction of three-dimensional flapping wings. AIAA J. 55 (3), 729–739.CrossRefGoogle 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, 177–195.CrossRefGoogle Scholar
Lua, K.B., Lu, H., Zhang, X.H., Lim, T.T. & Yeo, K.S. 2016 b Aerodynamics of two-dimensional flapping wings in tandem configuration. Phys. Fluids 28 (12), 121901.CrossRefGoogle Scholar
Lua, K.B., Zhang, X.H., Lim, T.T. & Yeo, K.S. 2015 Effects of pitching phase angle and amplitude on a two-dimensional flapping wing in hovering mode. Exp. Fluids 56, 1–22.CrossRefGoogle Scholar
Oh, S., Lee, B., Park, H., Choi, H. & Kim, S.-T. 2020 A numerical and theoretical study of the aerodynamic performance of a hovering rhinoceros beetle (trypoxylus dichotomus). J. Fluid Mech. 885, A18.CrossRefGoogle Scholar
Poelma, C., Dickson, W.B. & Dickinson, M.H. 2006 Time-resolved reconstruction of the full velocity field around a dynamically-scaled flapping wing. Exp. Fluids 41, 213–225.CrossRefGoogle Scholar
Shyy, W. & Liu, H. 2007 Flapping wings and aerodynamic lift: the role of leading-edge vortices. AIAA J. 45 (12), 2817–2819.CrossRefGoogle Scholar
Sinha, J., Lua, K.B. & Dash, S.M. 2021 Influence of the pivot location on the thrust and propulsive efficiency performance of a two-dimensional flapping elliptic airfoil in a forward flight. Phys. Fluids 33 (8), 081912.CrossRefGoogle Scholar
Sun, M. & Lan, S.L. 2004 A computational study of the aerodynamic forces and power requirements of dragonfly (aeschna juncea) hovering. J. Expl Biol. 207 (11), 1887–1901.CrossRefGoogle ScholarPubMed
Sun, M. & Tang, J. 2002 Unsteady aerodynamic force generation by a model fruit fly wing in flapping motion. J. Expl Biol. 205 (1), 55–70.CrossRefGoogle Scholar
Sun, M. & Wu, J. 2004 Large aerodynamic forces on a sweeping wing at low Reynolds number. Acta Mechanica Sin. 20 (1), 24–31.Google Scholar
Weis-Fogh, T. 1973 Quick estimates of flight fitness in hovering animals, including novel mechanisms for lift production. J. Expl Biol. 59 (1), 169–230.CrossRefGoogle Scholar
Werner, N.H., Chung, H., Wang, J., Liu, G., Cimbala, J.M., Dong, H. & Cheng, B. 2019 Radial planetary vorticity tilting in the leading-edge vortex of revolving wings. Phys. Fluids 31 (4), 041902.CrossRefGoogle Scholar
Wu, J., Chen, L., Zhou, C., Hsu, S.-J. & Cheng, B. 2019 Aerodynamics of a flapping-perturbed revolving wing. AIAA J. 57 (9), 3728–3743.CrossRefGoogle Scholar
Wu, J. & Sun, M. 2005 The influence of the wake of a flapping wing on the production of aerodynamic forces. Acta Mechanica Sin. 21 (5), 411–418.CrossRefGoogle Scholar
Wu, J.-Z., Ma, H.-Y. & Zhou, M.-D. 2007 Vorticity and Vortex Dynamics. Springer Science & Business Media.Google Scholar