Reaction-diffusion fronts in systems with concentration-dependent diffusivities.
We examine properties of a reaction front that forms in irreversible reaction-diffusion systems with concentration-dependent diffusivities. We study two different models of such systems and find that in the limit of a vanishingly small diffusivity of the reaction product, the reaction front dynamics enters a separate universality class, with the front width asymptotically tending to a constant value, and the reaction rate at the reaction front center diminishing with time t as t(-1/2). This behavior can be also observed in systems with nonvanishing (but small) diffusivity of the reaction product at intermediate times.
Polanowski
Piotr
P
Department of Molecular Physics, Technical University of Łódź, Zeromskiego 116, 90-924 Łódź, Poland.
Koza
Zbigniew
Z