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Updated: Jun 23, 2026
10:56
Confocal Imaging of Confined Quiescent and Flowing Colloid-polymer Mixtures
Published on: May 20, 2014
Particle segregation and dynamics in confined flows.
Dino Di Carlo1, Jon F Edd, Katherine J Humphry
1BioMEMS Resource Center, Massachusetts General Hospital, and Harvard Medical School, Boston, Massachusetts 02114, USA. dicarlo@seas.ucla.edu
Physical Review Letters
|April 28, 2009
Summary
Nonlinear fluid dynamics cause particles to migrate across flow streamlines. In highly confined channels, this leads to unique particle behaviors and complex lift force scaling with geometry.
Area of Science:
- Fluid dynamics
- Particle dynamics
- Microfluidics
Background:
- Nonlinearity in fluid flow at finite Reynolds numbers causes particle migration.
- The tubular pinch effect describes particle migration transverse to streamlines in cylindrical pipes.
Purpose of the Study:
- Investigate nonlinear effects in highly confined systems.
- Analyze particle dynamics where particle size approaches channel dimensions.
Main Methods:
- Experimental investigation of particle migration.
- Numerical simulations of fluid-particle interactions.
Main Results:
- Observed distinctive particle dynamics in confined geometries.
- Revealed complex scaling of lift forces with channel and particle geometry.
Conclusions:
- Unique behaviors arise in highly confined particulate flows.
- Findings have broad implications for understanding and manipulating micro-particle transport.
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