Session MM - Chaos and Fractals.
MIXED session, Tuesday afternoon, November 23
Whidbey, Westin Seattle
Experiments are performed on the effects of active mixing on the dynamics of a vortex chain. The process is called “self-consistent” because of its circular nature: the mixing affects the time-dependence of the flow which, in turn, affects the mixing. The flow is forced magnetohydrodynamically -- an electrical current passes through a salt-water solution and interacts with an alternating magnetic field to generate a chain of vortices. The system is forced with a current below that for time-dependent oscillations. A more concentrated salt solution is injected as the active impurity. An instability arises in which blobs of more- and less-concentrated salt solution are advected around the vortices, causing oscillations in the vortex boundaries and leading to chaotic mixing of impurities between vortices.