Propagation of a chemical wave front in a quasi-two-dimensional superdiffusive flow

• Published in: Physical review. E, Statistical, nonlinear, and soft matter physics Vol. 81; no. 6 Pt 2; p. 066211
• Main Authors: von Kameke, A, Huhn, F, Fernández-García, G, Muñuzuri, A P, Pérez-Muñuzuri, V
• Format: Journal Article
• Language: English
• Published: United States 18-06-2010
• ISSN: 1539-3755; 1550-2376
• DOI: 10.1103/physreve.81.066211

Pattern formation in reaction-diffusion systems is an important self-organizing mechanism in nature. Dynamics of systems with normal diffusion do not always reflect the processes that take place in real systems when diffusion is enhanced by a fluid flow. In such reaction-diffusion-advection systems diffusion might be anomalous for certain time and length scales. We experimentally study the propagation of a chemical wave occurring in a Belousov-Zhabotinsky reaction subjected to a quasi-two-dimensional chaotic flow created by the Faraday experiment. We present a novel analysis technique for the local expansion of the active wave front and find evidence of its superdiffusivity. In agreement with these findings the variance σ(2)(t)∝t(γ) of the reactive wave grows supralinear in time with an exponent γ>2. We study the characteristics of the underlying flow with microparticles. By statistical analysis of particle trajectories we derive flight time and jump length distributions and find evidence that tracer-particles undergo complex trajectories related to Lévy statistics. The propagation of active and passive media in the flow is compared.