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Updated: Aug 13, 2026
10:03
The Preparation of Electrohydrodynamic Bridges from Polar Dielectric Liquids
Published on: September 30, 2014
Particle-Induced Electroconvection in Nonpolar Liquids
Leyun Feng1, Diptendu Sen2, Zhanwen Wang3
1Department of Engineering Sciences and Applied Mathematics, McCormick School of Engineering and Applied Science, Northwestern University, Evanston, Illinois60208, United States.
Langmuir : the ACS Journal of Surfaces and Colloids
|August 11, 2026
Summary
Electrohydrodynamic (EHD) flow emerges around colloidal particles in oil under a DC electric field, driven by the Onsager-Wien effect. This phenomenon enables particle self-assembly and directed motion, opening new avenues for microfluidic control.
Area of Science:
- Colloid science
- Fluid dynamics
- Electrokinetics
Background:
- Understanding particle behavior in electric fields is crucial for microfluidics.
- The Onsager-Wien effect describes charge generation in non-uniform electric fields.
Purpose of the Study:
- To investigate electrohydrodynamic (EHD) flow around colloidal particles in oil under a DC electric field.
- To explore the influence of particle conductivity on flow patterns.
- To validate experimental findings with theoretical predictions.
Main Methods:
- Subjecting oil suspensions of colloidal particles to a uniform DC electric field.
- Observing and analyzing the resulting fluid flow patterns around individual particles.
- Comparing experimental results with theoretical models.
Main Results:
- Observed EHD flow around colloidal particles attributed to the Onsager-Wien effect.
- Quadrupolar flow patterns around conducting particles, distinct from induced-charge electro-osmosis.
- Complex flow structures around insulating particles.
- Quantitative agreement between experimental data and theoretical predictions.
Conclusions:
- The Onsager-Wien effect is a key mechanism driving EHD flow around colloidal particles.
- EHD flow can be controlled by particle properties, influencing particle dynamics.
- This EHD flow offers potential for particle self-assembly and directed transport applications.
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