Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published November 2007 | public
Journal Article

A potential-flow, deformable-body model for fluid–structure interactions with compact vorticity: application to animal swimming measurements


This paper presents an approach to quantify the unsteady fluid forces, moments and mass transport generated by swimming animals, based on measurements of the surrounding flow field. These goals are accomplished within a framework that is independent of the vorticity field, making it unnecessary to directly resolve boundary layers on the animal, body–vortex interactions, or interactions among vortex lines in the wake. Instead, the method identifies Lagrangian coherent structures in the flow, whose dynamics in flows with compact vorticity are shown to be well approximated by potential flow concepts, especially the Kirchhoff and deformation potentials from deformable body theory. Examples of the application of these methods are given for pectoral fin locomotion of the bluegill sunfish and undulatory swimming of jellyfish, and the methods are validated by analysis of a canonical starting vortex ring flow. The transition to a Lagrangian approach toward animal swimming measurements suggests the possibility of implementing recently developed particle tracking (vis-à-vis DPIV) techniques for fully three-dimensional measurements of animal swimming.

Additional Information

© 2007 Springer-Verlag. Received: 12 February 2007; Revised: 3 April 2007; Accepted: 13 April 2007; Published online: 8 August 2007. The authors are grateful for collaborations on this work with J.E. Marsden, S.C. Shadden, G.V. Lauder, P.G. Madden, M. Rosenfeld, E. Franco, D.N. Pekarek, and K. Katija. This research is supported by a grant from the Ocean Sciences Division, Biological Oceanography Program at NSF (OCE 0623475) to J.O.D.

Additional details

August 19, 2023
October 23, 2023