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Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
Nonequilibrium sedimentation of colloids on the particle scale
C Patrick Royall1, Joachim Dzubiella, Matthias Schmidt
1Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan.
Physical Review Letters
|May 16, 2007
Summary
We studied colloidal dispersions in capillaries, finding agreement between experiments and simulations for density and pressure. Complex patterns formed when systems were out of equilibrium, revealing single-particle behavior.
Area of Science:
- Colloid and interface science
- Soft matter physics
- Computational fluid dynamics
Background:
- Colloidal dispersions are ubiquitous in nature and industry.
- Understanding particle behavior in confined geometries is crucial for material design.
- Sedimentation dynamics in confined systems remain complex to model.
Purpose of the Study:
- To investigate the sedimentation of hard-sphere-like colloidal dispersions in horizontal capillaries.
- To compare experimental results with theoretical and simulation predictions.
- To explore the formation of patterns in non-equilibrium systems.
Main Methods:
- Laser scanning confocal microscopy for experimental observation.
- Dynamical density functional theory (DDFT) for theoretical modeling.
- Brownian dynamics (BD) computer simulations for particle-level analysis.
Main Results:
- Quantitative agreement between microscopy, DDFT, and BD for density distribution and wall pressure in homogenized systems.
- Observation of complex lateral pattern formation when systems are initialized far from equilibrium.
- Demonstration of experimental accessibility of single-particle information even in complex, non-equilibrium states.
Conclusions:
- The combination of experimental and computational methods provides a robust framework for studying confined colloidal systems.
- Non-equilibrium conditions can lead to emergent complex structures in colloidal dispersions.
- Single-particle dynamics can be probed experimentally in intricate colloidal pattern formation.
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