Chaos-enhanced transport in cellular flows

Abstract

Examples of chaos-enhanced transport in cellular (lows are presented. Illustrations span from boundary and jet induced motions within cavities to separated flows; chaotic adveetion is generated by time-modulation of walls, variation of angle of impingement of laminar jets, and naturally occurring oscillations in the velocity field as the Reynolds number is increased. Tools include manifold structure, the Melnikov technique, as well as eulerian and lagrangian descriptions of transport. A range of Peclet numbers is explored; the amount of transport enhancement over the nonchaotic case is exemplified in terms of heating of a fluid and the removal of a diffusive tracer; the enhancement over the non chaotic case can be as large as 40%.