Journal article
Elliptic random-walk equation for suspension and tracer transport in porous media
Center for Phase Equilibria and Separation Processes, Department of Chemical and Biochemical Engineering, Technical University of Denmark1
Department of Chemical and Biochemical Engineering, Technical University of Denmark2
University of Adelaide3
Center for Energy Resources Engineering, Centers, Technical University of Denmark4
We propose a new approach to transport of the suspensions and tracers in porous media. The approach is based on a modified version of the continuous time random walk (CTRW) theory. In the framework of this theory we derive an elliptic transport equation. The new equation contains the time and the mixed dispersion terms expressing the dispersion of the particle time steps.
The properties of the new equation are studied and the fundamental analytical solutions are obtained. The solution of the pulse injection problem describing a common tracer injection experiment is studied in greater detail. The new theory predicts delay of the maximum of the tracer, compared to the velocity of the flow, while its forward "tail" contains much more particles than in the solution of the classical parabolic (advection-dispersion) equation.
This is in agreement with the experimental observations and predictions of the CTRW theory. (C) 2008 Elsevier B.V. All rights reserved.
| Language: | English |
|---|---|
| Year: | 2008 |
| Pages: | 5963-5978 |
| ISSN: | 18732119 and 03784371 |
| Types: | Journal article |
| DOI: | 10.1016/j.physa.2008.07.013 |
| ORCIDs: | Shapiro, Alexander |
