University of Minnesota
Aerospace Engineering and Mechanics
Winter 1998 Seminar Series



Dynamics in the Cylinder's Wake


Dwight Barkley
Deputy Director of MIR@W
(Mathematical Interdisciplinary Research at Warwick)

University of Warwick
Currently visiting The Institute of Mathematics and its Applications
University of Minnesota


Abstract


This talk focuses on a non-steady (Floquet) stability analysis of the wake of a circular cylinder with a view to understanding the scenario leading to chaos (weak turbulence) in wake flows. A flexible, highly accurate computational method based on spectral elements is described. Using this method the secondary instability of the cylinder wake, at which the two-dimensional wake becomes three-dimensionally unstable, is determined to high precision. A computational nonlinear stability analysis is presented showing that this instability is subcritical. Finally, based on the numerical computations a dynamical-systems model is proposed that captures most features of 3D wake transition.

Friday, March 6, 1998
209 Akerman Hall
2:30-3:30 p.m.


Refreshments served after the seminar in 227 Akerman Hall.
Disability accomodations provided upon request.
Contact Audrey Stark-Evers, Senior Secretary, 625-8000.