Resonant chaotic mixing in a cellular flow.

This Letter presents a quantitative theory of resonant mixing in time-dependent volume-preserving 3D flows using a model cellular flow introduced in T. Solomon and I. Mezic, Nature (London) 425, 376 (2003), as an example. Specifically, we show that chaotic advection is dramatically enhanced by a time-dependent perturbation for certain resonant frequencies. We compute the fraction of the mixed volume as a function of the frequency of the perturbation and show that essentially complete mixing in 3D is achieved at every resonant frequency.