Session MM - Chaos and Fractals.
MIXED session, Tuesday afternoon, November 23
Whidbey, Westin Seattle
We show that in generic situations a reversible periodic driving of a low-Reynolds number flow will not result in a reversible flow field. In the famous experiment of GI Taylor with a blob of dye between concentric cylinders only a single eigenmode of the Stokes operator is involved and reversibility is assured. In generic situations several modes are present and since each eigenmode responds with a phase delay that depends on its eigenvalue and the driving frequency, not all modes will be in phase anymore. Such a viscous dephasing then breaks time reversal symmetry. The general theory is illustrated for 2-d vortex patterns that can be generated in current driven flows in a magnetic field.