Comptes Rendus
Control of the separated flow around an airfoil using a wavy leading edge inspired by humpback whale flippers
Comptes Rendus. Mécanique, Volume 340 (2012) no. 1-2, pp. 107-114.

The influence of spanwise geometrical undulations of the leading edge of an infinite wing is investigated numerically at low Reynolds number, in the context of passive separation control and focusing on the physical mechanisms involved. Inspired by the tubercles of the humpback whale flippers, the wavy leading edge is modeled using a spanwise sinusoidal function whose amplitude and wavelength constitute the parameters of control. A direct numerical simulation is performed on a NACA0020 wing profile in a deep stall configuration (α=20°), with and without the presence of the leading edge waviness. The complex solid boundaries obtained by varying the sinusoidal shape of the leading edge are modeled using an immersed boundary method (IBM) recently developed by the authors [Pinelli et al., J. Comput. Phys. 229 (2010) 9073–9091]. A particular set of wave parameters is found to change drastically the topology of the separated zone, which becomes dominated by streamwise vortices generated from the sides of the leading edge bumps. A physical analysis is carried out to explain the mechanism leading to the generation of these coherent vortical structures. The role they play in the control of boundary layer separation is also investigated, in the context of the modifications of the hydrodynamic performances which have been put forward in the literature in the last decade.

Lʼinfluence dʼondulations géométriques le long du bord dʼattaque dʼun profil dʼaile est étudiée numériquement à faible nombre de Reynolds, dans une optique de contrôle passif du décollement et en se focalisant sur les mécanismes physiques mis en jeu. Inspiré des tubercules présents sur les ailerons des baleines à bosse, ce bord dʼattaque ondulé est modelisé par une sinusoïde le long de lʼenvergure, dont la longueur dʼonde et lʼamplitude constituent les paramètres de contrôle. Une simulation numérique directe est effectuée sur un profil NACA0020 dans une configuration dʼécoulement décroché (α=20°), avec et sans ondulation de bord dʼattaque. Les frontières solides complexes engendrées par la variation des paramètres de lʼondulation géométrique sont traitées par la méthode des frontières immergées (IBM). Les noyaux des opérateurs dʼinterpolation/diffusion sont construits en utilisant la méthode RKPM (Pinelli et al., 2010 [12]). Une étude paramétrique permet dʼextraire un jeu de paramètres dʼondulation qui amène à une modification significative de la topologie de lʼécoulement décollé, qui se retrouve dominé par des tourbillons orientés vers lʼaval et générés sur les cotés des protubérances de bord dʼattaque. Une analyse physique est menée pour expliquer le mécanisme de formation de ces structures cohérentes tourbillonnaires. Le rôle quʼelles jouent dans le contrôle du décollement de couche limite est étudié également, sous lʼéclairage des modifications de performances hydrodynamiques présentées dans la litterature au cours de la dernière décennie.

Published online:
DOI: 10.1016/j.crme.2011.11.004
Keywords: Flow control, Biomimetics, Immersed boundary, Humpback whale flippers
Mot clés : Contrôle dʼécoulements, Biomimétisme, Méthode des frontières immergées, Ailerons de baleines à bosse

Julien Favier 1; Alfredo Pinelli 1; Ugo Piomelli 2

1 CIEMAT, Unidad de Modelización y Simulación Numérica, 28040 Madrid, Spain
2 Dept. of Mechanical and Materials Engineering, Queenʼs University, Kingston (Ontario) K7L 3N6, Canada
@article{CRMECA_2012__340_1-2_107_0,
     author = {Julien Favier and Alfredo Pinelli and Ugo Piomelli},
     title = {Control of the separated flow around an airfoil using a wavy leading edge inspired by humpback whale flippers},
     journal = {Comptes Rendus. M\'ecanique},
     pages = {107--114},
     publisher = {Elsevier},
     volume = {340},
     number = {1-2},
     year = {2012},
     doi = {10.1016/j.crme.2011.11.004},
     language = {en},
}
TY  - JOUR
AU  - Julien Favier
AU  - Alfredo Pinelli
AU  - Ugo Piomelli
TI  - Control of the separated flow around an airfoil using a wavy leading edge inspired by humpback whale flippers
JO  - Comptes Rendus. Mécanique
PY  - 2012
SP  - 107
EP  - 114
VL  - 340
IS  - 1-2
PB  - Elsevier
DO  - 10.1016/j.crme.2011.11.004
LA  - en
ID  - CRMECA_2012__340_1-2_107_0
ER  - 
%0 Journal Article
%A Julien Favier
%A Alfredo Pinelli
%A Ugo Piomelli
%T Control of the separated flow around an airfoil using a wavy leading edge inspired by humpback whale flippers
%J Comptes Rendus. Mécanique
%D 2012
%P 107-114
%V 340
%N 1-2
%I Elsevier
%R 10.1016/j.crme.2011.11.004
%G en
%F CRMECA_2012__340_1-2_107_0
Julien Favier; Alfredo Pinelli; Ugo Piomelli. Control of the separated flow around an airfoil using a wavy leading edge inspired by humpback whale flippers. Comptes Rendus. Mécanique, Volume 340 (2012) no. 1-2, pp. 107-114. doi : 10.1016/j.crme.2011.11.004. https://comptes-rendus.academie-sciences.fr/mecanique/articles/10.1016/j.crme.2011.11.004/

[1] D.M. Bushnell; K.J. Moore Drag reduction in nature, Annu. Rev. Fluid Mech., Volume 23 (1991), pp. 65-79

[2] F.M. Fish; J.M. Battle Hydrodynamic design of the humpback whale flipper, J. Morphology, Volume 225 (1995), pp. 51-60

[3] P. Watts, F.E. Fish, The influence of passive, leading edge tubercles on wing performance, in: Proc. 12th UUST, Durham, New Hampshire, August 2001.

[4] D.S. Miklosovic; M.M. Murray; L.E. Howle; F.E. Fish Leading-edge tubercles delay stall on humpback whale (Megaptera novaeangliae) flippers, Phys. Fluids, Volume 16 (2004) no. 5, pp. 39-42

[5] H. Johari; C. Henoch; D. Cosutodio; A. Levshin Effects of leading-edge protuberances on airfoil performance, AIAA J., Volume 45 (2007) no. 11, pp. 2634-2642

[6] M.J. Stanway, Hydrodynamic effects of leading-edge tubercles on control surfaces and in flapping foil propulsion, PhD thesis, MIT, 2008.

[7] E.G. Paterson; R.V. Wilson; F. Stern General-purpose parallel unsteady RANS CFD code for ship hydrodynamics, IIHR Hydrosci. Eng. Rep., Volume 531 (2003) (Univ. Iowa, Iowa)

[8] E.A. van Nierop; S. Alben; M.P. Brenner How bumps on whale flippers delay stall: An aerodynamic model, Phys. Rev. Lett., Volume 100 (2008), p. 054502

[9] F.E. Fish; G.V. Lauder Passive and active flow control by swimming fishes and mammals, Annu. Rev. Fluid Mech., Volume 38 (2006), pp. 193-224

[10] R. Bourguet; M. Braza; A. Sevrain; A. Bouhadji Capturing transition features around a wing by reduced-order modeling based on compressible Navier–Stokes equations, Phys. Fluids, Volume 21 (2009), p. 094104

[11] C.S. Peskin Flow patterns around heart valves: a numerical method, J. Comput. Phys., Volume 10 (1972), pp. 252-271

[12] A. Pinelli; I.Z. Naqavi; U. Piomelli; J. Favier Immersed-boundary methods for general finite-difference and finite-volume Navier–Stokes solvers, J. Comput. Phys., Volume 229 (2010), pp. 9073-9091

[13] F.H. Harlow; E. Welch Numerical calculation of time-dependent viscous incompressible flow of fluid with free surface, Phys. Fluids, Volume 8 (1965) no. 12

[14] A.J. Chorin Numerical solution of Navier–Stokes equations, Math. Comput., Volume 22 (1968) no. 104, pp. 745-762

[15] J. Kim; P. Moin Application of a fractional step method to incompressible Navier–Stokes equations, J. Comput. Phys., Volume 59 (1985), pp. 308-323

[16] J. Van Kan A second-order accurate pressure-correction scheme for viscous incompressible flow, SIAM J. Sci. Stat. Comput., Volume 7 (1986), pp. 870-891

[17] M. Uhlmann An immersed boundary method with direct forcing for the simulation of particulate flows, J. Comput. Phys., Volume 209 (2005) no. 2, pp. 448-476

[18] P.W. Weber; L.E. Howle; M.M. Murray; D.S. Miklosovic Computational evaluation of the performance of lifting surfaces with leading edge protuberances, J. Aircraft, Volume 48 (2011), pp. 591-600

[19] F.E. Fish; P.W. Weber; M.M. Murray; L.E. Howle The humpback whaleʼs flipper: Application of bio-inspired tubercle technology, Integrative and Comparative Biology (2011)

[20] J.C.R. Hunt; A.A. Wray; P. Moin Eddies, streams, and convergence zones in turbulent flows, Studying Turbulence Using Numerical Simulation Databases, 2, Proceedings of the 1988 Summer Program, Stanford University, 1988, pp. 193-208

[21] Y. Dubief; F. Delcayre On coherent-vortex identification in turbulence, J. Turbulence, Volume 1 (2000), pp. 1-22

[22] G. Kawahara; J. Jimenez; M. Uhlmann; A. Pinelli Linear instability of a corrugated vortex sheet – a model for streak instability, J. Fluid Mech., Volume 483 (2003), pp. 315-342

Cited by Sources:

Comments - Policy