Hostname: page-component-745bb68f8f-cphqk Total loading time: 0 Render date: 2025-01-20T17:42:39.209Z Has data issue: false hasContentIssue false
  • English
  • Français

How dorsal fin sharpness affects swimming speed and economy

Published online by Cambridge University Press:  10 September 2019

Qiang Zhong Open the ORCID record for Qiang Zhong [Opens in a new window] ,
Haibo Dong  and
Daniel B. Quinn
Qiang Zhong*
Affiliation:
Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA 22904, USA
Haibo Dong
Affiliation:
Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA 22904, USA
Daniel B. Quinn
Affiliation:
Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA 22904, USA Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA 22904, USA
*
†Email address for correspondence: qz4te@virginia.edu
Get access Rights & Permissions [Opens in a new window]

Abstract

Multi-fin systems, like fish or fish-inspired vehicles, are governed by unsteady three-dimensional interactions between their multiple fins. In particular, dorsal/anal fins have received much attention because they are just upstream of the main thrust-producing fin: the caudal (tail) fin. We used a tuna-inspired fish model with variable fin sharpness to study the interaction between elongated dorsal/anal fins and caudal fins. We found that the performance enhancement is stronger than previously thought (15 % increase in swimming speed and 50 % increase in swimming economy) and is governed by a three-dimensional dorsal-fin-induced cross-flow that lowers the angle of attack on the caudal fin and promotes spanwise flow. Both simulations and multi-layer particle image velocimetry reveal that the cross-flow stabilizes the leading edge vortex on the caudal fin, similar to how wing strakes prevent stall during fixed-wing aircraft manoeuvres. Unlike other fin–fin interactions, this mechanism is phase-insensitive and offers a simple, passive solution for flow control over oscillating propulsors. Our results therefore improve our understanding of multi-fin flow interactions and suggest new insights into dorsal/anal fin shape and placement in fish and fish-inspired vehicles.

JFM classification

Biological Fluid Dynamics: Swimming/flying Biological Fluid Dynamics: Propulsion Vortex Flows: Vortex interactions
Type
JFM Papers
Information
Journal of Fluid Mechanics , Volume 878 , 10 November 2019 , pp. 370 - 385
Copyright
© 2019 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

Akhtar, I., Mittal, R., Lauder, G. V. & Drucker, E. 2007 Hydrodynamics of a biologically inspired tandem flapping foil configuration. Theor. Comput. Fluid Dyn. 21 (3), 155–170.Google Scholar
Aleev, I. U.1969 Function and Gross Morphology in Fish. Keter Press.Google Scholar
Bainbridge, R. 1958 The speed of swimming of fish as related to size and to the frequency and amplitude of the tail beat. J. Exp. Biol. 35 (1), 109–133.Google Scholar
Bode-Oke, A. T., Zeyghami, S. & Dong, H. 2017 Aerodynamics and flow features of a damselfly in takeoff flight. Bioinspir. Biomim. 12 (5), 056006.Google Scholar
Borazjani, I. & Daghooghi, M. 2013 The fish tail motion forms an attached leading edge vortex. Proc. R. Soc. Lond. B 280 (1756), 20122071.Google Scholar
Borazjani, I. & Sotiropoulos, F. 2010 On the role of form and kinematics on the hydrodynamics of self-propelled body/caudal fin swimming. J. Exp. Biol. 213 (1), 89–107.Google Scholar
Boschitsch, B. M., Dewey, P. A. & Smits, A. J. 2014 Propulsive performance of unsteady tandem hydrofoils in an in-line configuration. Phys. Fluids 26 (5), 051901.Google Scholar
Collette, B. B. & Nauen, C. E.1983 FAO Species Catalogue. Volume 2. Scombrids of the World. An Annotated and Illustrated Catalogue of Tunas, Mackerels, Bonitos and Related Species Known to Date. Food and Agriculture Organization of the United Nations.Google Scholar
Daghooghi, M. & Borazjani, I. 2015 The hydrodynamic advantages of synchronized swimming in a rectangular pattern. Bioinspir. Biomim. 10 (5), 056018.Google Scholar
Dewey, P. A., Quinn, D. B., Boschitsch, B. M. & Smits, A. J. 2014 Propulsive performance of unsteady tandem hydrofoils in a side-by-side configuration. Phys. Fluids 26 (4), 041903.Google Scholar
Drucker, E. G. & Lauder, G. V. 2001 Locomotor function of the dorsal fin in teleost fishes: experimental analysis of wake forces in sunfish. J. Exp. Biol. 204 (17), 2943–2958.Google Scholar
Eldredge, J. D. & Jones, A. R. 2019 Leading-edge vortices: mechanics and modeling. Annu. Rev. Fluid Mech. 51, 75–104.Google Scholar
Fernández-Prats, R., Raspa, V., Thiria, B., Huera-Huarte, F. & Godoy-Diana, R. 2015 Large-amplitude undulatory swimming near a wall. Bioinspir. Biomim. 10 (1), 016003.Google Scholar
Fish, F. E., Goetz, K. T., Rugh, D. J. & Brattström, L. V. 2013 Hydrodynamic patterns associated with echelon formation swimming by feeding bowhead whales (balaena mysticetus). Marine Mammal Sci. 29 (4), E498–E507.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
Iglisch, R.1949 Exact calculation of laminar boundary layer in longitudinal flow over a flat plate with homogeneous suction. NACA-TM-1205. NACA.Google Scholar
Jardin, T. 2017 Coriolis effect and the attachment of the leading edge vortex. J. Fluid Mech. 820, 312–340.Google Scholar
Lauder, G. V. & Madden, P. G. A. 2008 Advances in comparative physiology from high-speed imaging of animal and fluid motion. Annu. Rev. Physiol. 70, 143–163.Google Scholar
Lentink, D. & Dickinson, M. H. 2009 Rotational accelerations stabilize leading edge vortices on revolving fly wings. J. Exp. Biol. 212 (16), 2705–2719.Google Scholar
Lindsey, C. C. 1978 Form, function and locomotory habits in fish. In Locomotion (ed. Hoar, W. S. & Randall, D. J.), Fish Physiology, vol. VII, pp. 1–100. Elsevier.Google Scholar
Liu, G., Ren, Y., Dong, H., Akanyeti, O., Liao, J. C. & Lauder, G. V. 2017 Computational analysis of vortex dynamics and performance enhancement due to body–fin and fin–fin interactions in fish-like locomotion. J. Fluid Mech. 829, 65–88.Google Scholar
Magnuson, J. J. 1970 Hydrostatic equilibrium of Euthynnus affinis, a pelagic teleost without a gas bladder. Copeia 1, 56–85.Google Scholar
Manar, F., Mancini, P., Mayo, D. & Jones, A. R. 2015 Comparison of rotating and translating wings: force production and vortex characteristics. AIAA J. 54 (2), 519–530.Google Scholar
Mancini, P., Manar, F., 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
Nashimoto, K. 1980 The swimming speed of fish in relation to fish size and frequency of tail beating. Nippon Suisan Gakkaishi 46 (3), 307–312.Google Scholar
Nauen, J. C. & Lauder, G. V. 2002 Hydrodynamics of caudal fin locomotion by Chub Mackerel, Scomber Japonicus (scombridae). J. Exp. Biol. 205 (12), 1709–1724.Google Scholar
Quinn, D. B., Moored, K. W., Dewey, P. A. & Smits, A. J. 2014 Unsteady propulsion near a solid boundary. J. Fluid Mech. 742, 152–170.Google Scholar
Reznick, S. G. & Flores, J. 1989 Strake-generated vortex interactions for a fighter-like configuration. J. Aircraft 26 (4), 289–294.Google Scholar
Rohr, J. J. & Fish, F. E. 2004 Strouhal numbers and optimization of swimming by odontocete cetaceans. J. Exp. Biol. 207 (10), 1633–1642.Google Scholar
Rudolph, P. K. C.1996 High-lift systems on commercial subsonic airliners. NASA-CR-4746. NASA.Google Scholar
Saadat, M., Fish, F. E., Domel, A. G., Di Santo, V., Lauder, G. V. & Haj-Hariri, H. 2017 On the rules for aquatic locomotion. Phys. Rev. Fluids 2 (8), 083102.Google Scholar
Shah, G. 1991 Wind tunnel investigation of aerodynamic and tail buffet characteristics of leading-edge extension modifications to the f/a-18. In 18th Atmospheric Flight Mechanics Conference, p. 2889. American Institute of Aeronautics and Astronautics.Google Scholar
Smith, A. M. O. 1975 High-lift aerodynamics. J. Aircraft 12 (6), 501–530.Google Scholar
Standen, E. M. & Lauder, G. V. 2007 Hydrodynamic function of dorsal and anal fins in brook trout (salvelinus fontinalis). J. Exp. Biol. 210 (2), 325–339.Google Scholar
Tytell, E. D. 2006 Median fin function in bluegill sunfish Lepomis macrochirus: streamwise vortex structure during steady swimming. J. Exp. Biol. 209 (8), 1516–1534.Google Scholar
Walters, V. 1962 Body form and swimming performance in the scombroid fishes. Am. Zool. 2, 143–149.Google Scholar
White, F. M. & Corfield, I. 2006 Viscous Fluid Flow, vol. 3. McGraw-Hill.Google Scholar
Zeyghami, S., Zhong, Q., Liu, G. & Dong, H. 2018 Passive pitching of a flapping wing in turning flight. AIAA J. doi:10.2514/1.J056622.Google Scholar
Zhong, Q., Liu, G., Ren, Y. & Dong, H. 2017 On the passive pitching mechanism in turning flapping flights using a torsional spring model. In 47th AIAA Fluid Dynamics Conference, p. 3817. American Institute of Aeronautics and Astronautics.Google Scholar
Zhu, Q., Wolfgang, M. J., Yue, D. K. P. & Triantafyllou, M. S. 2002 Three-dimensional flow structures and vorticity control in fish-like swimming. J. Fluid Mech. 468, 1–28.Google Scholar

Zhong Supplementary Movie

3D PIV reveals that dorsal fin stabilizes the flow over caudal fin in M4 case compare to M1 case.

Download Zhong Supplementary Movie(Video)
Video 25 MB