The next Physics Seminar speaker, Tom Solomon of Bucknell University, will present "Chaotic Mixing and Reaction Patterns" on Tuesday, March 4, at noon in CNS 204. Pizza and refreshments will be provided.
Please bring your own cup. "Reduce, reuse, recycle" for a sustainable campus!
Abstract: "Chaotic Mixing and Reaction Patterns"
Tracers moving in very simple fluid flows can undergo chaotic trajectories -- very complicated paths that show "sensitive dependence on initial conditions." We present experiments and numerical simulations of study chaotic fluid mixing in very simple vortex (whirlpool) flows. We also present experiments that demonstrate how chaotic mixing can affect the behavior of reactions occurring in the flow.
The particular reaction studied is the well-known Belousov-Zhabotinsky reaction, a reaction that oscillates for hours when well mixed, but which produces either traveling fronts or spiral/target patterns in an extended system. We find that chaotic mixing due to the vortex flow causes "mode-locking" of the propagating fronts. Reaction patterns that form mimic the patterns that describe chaotic mixing.
We also find that superdiffusive chaotic mixing (which is associated with a strange trajectory called a "Levy flight") causes synchronization of the oscillations over large distances.
https://www.ithaca.edu/intercom/article.php/20080228140932410