The uniform capillary model for packed beds and particle wettability
Nate Stevens1, John Ralston, Rossen Sedev
1Ian Wark Research Institute, University of South Australia, Mawson Lakes, SA 5095, Australia.
Journal of Colloid and Interface Science
|June 3, 2009
Summary
This study introduces a new method to measure advancing and receding contact angles in porous media using capillary pressure. The technique reliably determines these angles by accounting for porosity and trapped liquids in packed beds.
Area of Science:
- Fluid dynamics
- Materials science
- Physical chemistry
Background:
- Fluid flow in porous media is crucial for natural and industrial processes like oil recovery and filtration.
- Accurate measurement of contact angles is essential for understanding fluid behavior in these systems.
- Existing methods for contact angle determination in porous media present challenges.
Purpose of the Study:
- To develop and validate a novel methodology for deriving advancing and receding contact angles from capillary pressure measurements.
- To address the complexities of measuring contact angles in partially saturated packed beds.
- To provide a reliable approach for contact angle determination in various particulate systems.
Main Methods:
- Utilizing capillary pressure measurements in packed beds of particles.
- Modeling the porous medium as an equivalent uniform capillary.
- Implementing specific calibration steps for advancing and receding liquid fronts, including accounting for trapped liquids.
Main Results:
- Successfully performed capillary pressure measurements for both advancing and receding liquid fronts.
- Developed a method to calibrate the equivalent capillary radius using a second liquid for advancing contact angles.
- Established the necessity of determining trapped liquid volume for reliable receding contact angle measurements.
Conclusions:
- The proposed methodology provides a reliable way to measure advancing and receding contact angles in porous media.
- The method accounts for key factors like porosity and capillary retention.
- Validated with model systems, this technique is applicable to real-world particulate systems for enhanced fluid dynamics understanding.
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