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Published on: November 25, 2020
Model of dispersive transport across sharp interfaces between porous materials
1Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA. acortis@lbl.gov
Summary
Researchers explain solute transport asymmetry in porous media. Using Monte Carlo simulations, they reveal microscopic particle dynamics causing flux rectification, consistent with experimental findings on solute migration.
Area of Science:
- Environmental science
- Physical chemistry
- Chemical engineering
Background:
- Solute migration in composite porous columns exhibits unexplained arrival time asymmetry upon flow reversal.
- Current transport paradigms fail to account for observed phenomena in solute transport experiments.
Purpose of the Study:
- To define solute flux across sharp interfaces.
- To investigate the microscopic particle dynamics responsible for transport asymmetry.
- To provide a physical mechanism explaining the observed experimental results.
Main Methods:
- Monte Carlo simulations were employed to model particle dynamics.
- A novel definition for solute flux across sharp interfaces was proposed.
- Simulations were validated against previous experimental findings.
Main Results:
- The study successfully explains the observed asymmetry in solute arrival times.
- Microscopic particle dynamics reveal the mechanism behind flux rectification.
- Simulation results align with experimental data on solute migration.
Conclusions:
- The proposed definition of solute flux and the understanding of microscopic dynamics accurately explain transport asymmetry.
- The findings introduce a flux rectification mechanism for solute transport.
- The methodology is generalizable to other interfacial transport phenomena.
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