Transport phenomena in sharply contrasting media with a diffusion barrier

TL;DR

This paper analytically investigates how a diffusion barrier affects contaminant transport in contrasting media, revealing anomalous diffusion, exponential source attenuation, and altered concentration profiles.

Contribution

It introduces an analytical model for contaminant transport considering a diffusion barrier in contrasting media, highlighting new transport behaviors and regime crossovers.

Findings

Anomalous diffusion behavior observed.

Exponential attenuation of source power.

Modification of concentration distribution at large distances.

Abstract

Using the advection-diffusion equation, we analytically study contaminant transport in a sharply contrasting medium with a diffusion barrier due to localization of a contaminant source in a low-permeability medium. Anomalous diffusion behavior and crossover between different transport regimes are observed. The diffusion barrier results in exponential attenuation of the source power, retardation of the contaminant plume growth, and modification of the concentration distribution at large distances.