event
Monday 09 Jan 2012: Mixing of reactive tracers: spatial structures and the role of a delay time (Taylor and Francis Sponsored)
Alexandra Tzella - University of Edinburgh
203 15:00-16:00
Motivated by the spatial heterogeneity observed in plankton distributions in the ocean, we examine a class of reactive tracers that are mixed by a flow and maintained by a source, both of which are large-scale. Previous theoretical investigations have shown that, for large Peclet number, the structures are filamental and characterized by a single scaling regime that depends on the rate of convergence of the reactive processes and the strength of the stirring. Introducing a delay time in the reactions may result in two further scaling regimes that are unique to the delay system. An expression for the transition length-scale between the different regimes is obtained and the scaling behaviour of the tracer field is explained. We conclude with a discussion on the dependence of the field's scaling exponents on the stretching statistics.
