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Parameters Driving Anomalous Transport in Colloids: Dimensional Analysis
Bashar M Al-Zghoul1, William P Johnson2, Luis Ullauri2
1Department of Civil and Environmental Engineering and Earth Science, University of Notre Dame, Notre Dame, Indiana 46556, United States.
Langmuir : the ACS Journal of Surfaces and Colloids
|July 25, 2025
Summary
Surface charge heterogeneity significantly impacts colloid attachment efficiency (α) in porous media. A specific dimensionless group, Hr, dramatically influences α, driving transitions in colloid retention profiles.
Area of Science:
- Colloid and Surface Science
- Porous Media Transport
- Environmental Engineering
Background:
- Anomalous colloid transport exhibits multiexponential and nonmonotonic retention profiles.
- Understanding colloid attachment efficiency (α) is crucial for predicting transport behavior.
Purpose of the Study:
- To conduct a dimensional analysis of colloid transport equations.
- To identify dimensionless groups governing colloid attachment efficiency (α).
Main Methods:
- Dimensional analysis of governing equations.
- Pore-assembly colloid trajectory simulations.
- Categorization of dimensionless groups into hydrodynamic, DLVO, and surface charge heterogeneity.
Main Results:
- Fifteen dimensionless groups govern colloid transport.
- Surface charge heterogeneity groups dramatically influence α.
- The Hr group significantly impacts α between 0.6 < Hr < 2.
Conclusions:
- Surface charge heterogeneity is a dominant factor in colloid attachment.
- Variations in Hr drive changes in α and retention profiles.
- This work clarifies mechanisms behind anomalous colloid transport.
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