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Updated: Aug 15, 2025
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Confocal Imaging of Confined Quiescent and Flowing Colloid-polymer Mixtures
Published on: May 20, 2014
12.2K
Three-Dimensional Visualization Reveals Pore-Scale Mechanisms of Colloid Transport and Retention in Two-Phase Flow.
Ting Wu1,2,3, Zhibing Yang1,2, Ran Hu1,2
1State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan430072, China.
Environmental Science & Technology
|January 5, 2023
Summary
Colloid transport in two-phase flow is complex. This study visualizes how colloids aggregate or disperse based on flow rate and grain size, revealing crucial clogging mechanisms.
Area of Science:
- Environmental Science
- Geoscience
- Fluid Dynamics
Background:
- Colloids are vital for contaminant transport in nature.
- Two-phase flow complicates understanding colloid behavior.
- Detailed mechanisms of colloid transport and retention under two-phase flow remain unclear.
Purpose of the Study:
- To visualize and understand colloid transport and retention during immiscible two-phase flow.
- To investigate the influence of flow rate and pore/grain size on colloid behavior.
- To elucidate the underlying mechanisms of colloid clogging.
Main Methods:
- Confocal microscopy was used for visualization.
- Experiments involved immiscible two-phase flow.
- Theoretical analysis of pendular ring geometry was performed.
Main Results:
- Colloid transport and retention strongly depend on flow rate and grain size.
- At high flow rates, colloids aggregate in small-grain packings and disperse in large-grain packings.
- Colloids alter flow paths and wetting fluid topology, indicating two-way coupling.
Conclusions:
- The study elucidates the mechanism of colloid clogging, dependent on solid grain size.
- Colloid behavior significantly impacts two-phase flow dynamics.
- Improved predictive models are needed to account for colloid-induced clogging.
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