title: Anomalous transport regimes and asymptotic concentration distributions in the presence of advection and diffusion on a comb structure.
abstract: We study the transport of impurity particles on a comb structure in the presence of advection. The main body concentration and asymptotic concentration distributions are obtained. Seven different transport regimes occur on the comb structure with finite teeth: classical diffusion, advection, quasidiffusion, subdiffusion, slow classical diffusion, and two kinds of slow advection. Quasidiffusion deserves special attention. It is characterized by a linear growth of the mean-square displacement. However, quasidiffusion is an anomalous transport regime. We established that a change in transport regimes in time leads to a change in regimes in space. Concentration tails have a cascade structure, namely, consisting of several parts.
authors.affiliation: Nuclear Safety Institute, Russian Academy of Sciences, 52 Bolshaya Tul'skaya Street, 115191 Moscow, Russia.
authors.forename: Olga A
authors.initials: OA
authors.lastname: Dvoretskaya
authors.forename: Peter S
authors.initials: PS
authors.lastname: Kondratenko