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Continuous time random walk in homogeneous porous media
1Department of HydroSciences, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, China.
Journal of Contaminant Hydrology
|November 12, 2013
Summary
Continuous time random walk (CTRW) analysis reveals weak anomalous solute transport in homogeneous porous media. Anomalous behavior intensifies with increasing Peclet number (Pe), consistent with prior research.
Area of Science:
- Geophysics
- Chemical Engineering
- Physical Chemistry
Background:
- Continuous time random walk (CTRW) models anomalous transport in porous media.
- Simulations of solute transport in packed spheres are crucial for understanding fluid dynamics.
Purpose of the Study:
- To simulate and analyze solute transport in randomly packed spheres using CTRW.
- To investigate the influence of Peclet number (Pe) on anomalous transport.
- To explain non-Gaussian transport behavior through trapping probabilities.
Main Methods:
- Simulating solute transport in a porous medium composed of randomly packed spheres.
- Applying Continuous Time Random Walk (CTRW) models to analyze simulation data.
- Calculating trapping probabilities of solute particles in stagnant regions.
Main Results:
- Weak anomalous transport was observed in approximately homogeneous porous media.
- The degree of anomalous transport increased with higher Peclet numbers (Pe).
- Trapping probabilities in stagnant regions provided a physical basis for non-Gaussian behavior.
Conclusions:
- CTRW is effective for describing anomalous transport in porous media.
- Anomalous transport in homogeneous porous media is dependent on the Peclet number.
- Particle trapping in stagnant zones explains the observed non-Gaussian transport characteristics.
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