title: Kolmogorov-Sinai entropy for the A+B-->P reaction in transitional flows.
abstract: We study global decay of the bimolecular reaction A+B-->P as c(t) approximately t(-alpha) in a nonlinear transitional flow. A relationship is established between the decay exponent alpha, and a modified Kolmogorov-Sinai entropy, hr. We find that for dynamic conditions which induce relatively strong mixing, the decay exponent is alpha is proportional to ln psi(-Bhr) with B being a characteristic reactive mix-down time for the system, and psi is a space-time scaling parameter. Dynamic conditions which imply weak mixing lead to a degenerate dependence of alpha on hr. The proposed relationship between alpha on hr should be a useful link between the dynamical evolution of the flow field and reaction kinetics in vortex dominated flows.
authors.affiliation: Department of Physics, University of Oxford, United Kingdom. rogberg@atm.ox.ac.uk
authors.forename: P
authors.initials: P
authors.lastname: Rogberg
authors.forename: V
authors.initials: V
authors.lastname: Cvetkovic
mesh_terms: D019277:Entropy; D007700:Kinetics; D008433:Mathematics; D008956:Models, Chemical; D009038:Motion; D017711:Nonlinear Dynamics