Interdisciplinary Seminar in Nonlinear Science

Title: An Articulated Fish Swimming with Point Vortices
Speaker: Dr. Eva Kanso
Speaker Info: University of Southern California
Brief Description:
Special Note: More current information may be available at Plan-it Purple

Fish and cetaceans move in water with great agility through rhythmic unsteady motions of their body, fins and tail, and it is widely believed based on experimental evidence that fish exploit the unsteadiness in the flow to their advantage. Recently, we considered the problem of swimming in potential flow in an attempt to discern the fundamental principles of fish locomotion. Under these idealized conditions, that is, (in the absence of a vortex shedding mechanism}, we showed that a fish modeled as an articulated system of rigid links can propel and steer itself by only controlling its shape variables (the allowable relative rotations between the links). This result is important because, contrary to a common belief, it demonstrates that the forces and moments applied on the fish body by shed vortices are {not solely} responsible for the net locomotion. The net locomotion in potential flow occurs due to the transfer of momentum between the articulated body and the fluid. We are currently extending this reduced formulation to models that capture the complex interaction with point vortices so as to unravel the role of vorticity in aquatic locomotion and how fish exploit the presence of vortices to their locomotory advantage.
Date: Friday, December 02, 2005
Time: 2:00PM
Where: Tech M416
Contact Person: Mary Catsicopoulos
Contact email: maryc@northwestern.edu
Contact Phone: 847/491-5586
Copyright © 1997-2024 Department of Mathematics, Northwestern University.