QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online December 1, 2006
Journal of Experimental Biology 209, 4841-4857 (2006)
Published by The Company of Biologists 2006
doi: 10.1242/jeb.02526

This Article Figures Only Full Text Full Text (PDF) Supplementary Material Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in JEB Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kern, S. Articles by Koumoutsakos, P. Search for Related Content PubMed PubMed Citation Articles by Kern, S. Articles by Koumoutsakos, P. Social Bookmarking                         What's this?

Simulations of optimized anguilliform swimming

Stefan Kern and Petros Koumoutsakos^*

Institute of Computational Science, ETH Zurich, CH-8092, Switzerland

^* Author for correspondence (e-mail: petros{at}inf.ethz.ch)

Accepted 10 October 2006

The hydrodynamics of anguilliform swimming motions was investigated using three-dimensional simulations of the fluid flow past a self-propelled body. The motion of the body is not specified a priori, but is instead obtained through an evolutionary algorithm used to optimize the swimming efficiency and the burst swimming speed. The results of the present simulations support the hypothesis that anguilliform swimmers modify their kinematics according to different objectives and provide a quantitative analysis of the swimming motion and the forces experienced by the body.

The kinematics of burst swimming is characterized by the large amplitude of the tail undulations while the anterior part of the body remains straight. In contrast, during efficient swimming behavior significant lateral undulation occurs along the entire length of the body. In turn, during burst swimming, the majority of the thrust is generated at the tail, whereas in the efficient swimming mode, in addition to the tail, the middle of the body contributes significantly to the thrust. The burst swimming velocity is 42% higher and the propulsive efficiency is 15% lower than the respective values during efficient swimming.

The wake, for both swimming modes, consists largely of a double row of vortex rings with an axis aligned with the swimming direction. The vortex rings are responsible for producing lateral jets of fluid, which has been documented in prior experimental studies. We note that the primary wake vortices are qualitatively similar in both swimming modes except that the wake vortex rings are stronger and relatively more elongated in the fast swimming mode.

The present results provide quantitative information of three-dimensional fluid-body interactions that may complement related experimental studies. In addition they enable a detailed quantitative analysis, which may be difficult to obtain experimentally, of the different swimming modes linking the kinematics of the motion with the forces acting on the self-propelled body. Finally, the optimization procedure helps to identify, in a systematic fashion, links between swimming motion and biological function.

Key words: anguilliform swimming, hydrodynamics, fluid-body interaction, self-propelled, optimization, wake pattern

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

Related articles in JEB:

SWIMMING SECRETS

Laura Blackburn
JEB 2006 209: i. [Full Text]  

This article has been cited by other articles:

				M. A. Rapo, H. Jiang, M. A. Grosenbaugh, and S. Coombs Using computational fluid dynamics to calculate the stimulus to the lateral line of a fish in still water J. Exp. Biol., May 15, 2009; 212(10): 1494 - 1505. [Abstract] [Full Text] [PDF]

				C. M Postlethwaite, T. M Psemeneki, J. Selimkhanov, M. Silber, and M. A MacIver Optimal movement in the prey strikes of weakly electric fish: a case study of the interplay of body plan and movement capability J R Soc Interface, May 6, 2009; 6(34): 417 - 433. [Abstract] [Full Text] [PDF]

				I. Borazjani and F. Sotiropoulos Numerical investigation of the hydrodynamics of anguilliform swimming in the transitional and inertial flow regimes J. Exp. Biol., February 15, 2009; 212(4): 576 - 592. [Abstract] [Full Text] [PDF]

				A. A. Shirgaonkar, O. M. Curet, N. A. Patankar, and M. A. MacIver The hydrodynamics of ribbon-fin propulsion during impulsive motion J. Exp. Biol., November 1, 2008; 211(21): 3490 - 3503. [Abstract] [Full Text] [PDF]

				I. Borazjani and F. Sotiropoulos Numerical investigation of the hydrodynamics of carangiform swimming in the transitional and inertial flow regimes J. Exp. Biol., May 15, 2008; 211(10): 1541 - 1558. [Abstract] [Full Text] [PDF]

				E. D. Tytell and A. H. Cohen Rostral Versus Caudal Differences in Mechanical Entrainment of the Lamprey Central Pattern Generator for Locomotion J Neurophysiol, May 1, 2008; 99(5): 2408 - 2419. [Abstract] [Full Text] [PDF]

				L. Blackburn SWIMMING SECRETS J. Exp. Biol., December 15, 2006; 209(24): i - ii. [Full Text] [PDF]