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Preparation of Janus Particles and Alternating Current Electrokinetic Measurements with a Rapidly Fabricated Indium Tin Oxide Electrode Array
Published on: June 23, 2017
Competition between Dukhin's and Rubinstein's electrokinetic modes
H-C Chang1, E A Demekhin, V S Shelistov
1Department of Chemical and Biomolecular Engineering, Center for Microfluidics and Medical Diagnostics, University of Notre Dame, Notre Dame, Indiana 46556, USA.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 11, 2012
Summary
This study numerically investigates electroconvection, exploring how electro-osmotic flow and electrokinetic instability interact to enhance electric current. Findings reveal complex resonant interactions and potential suppression of instability by wall corrugation.
Area of Science:
- Electrokinetics
- Fluid Dynamics
- Nonlinear Systems
Background:
- Electrokinetic phenomena drive fluid motion and current enhancement at interfaces.
- Electroconvection involves coupled fluid flow and electric fields, crucial for microfluidic and electrochemical systems.
- Understanding the interplay of different electrokinetic modes is essential for optimizing device performance.
Purpose of the Study:
- To numerically investigate the combined effects of electro-osmotic flow (EOF) of the second kind and electrokinetic instability.
- To analyze the nonlinear coupling between these two electroconvection modes.
- To explore resonant interactions and the impact of wall corrugation on these phenomena.
Main Methods:
- Numerical simulations were employed to study the coupled nonlinear dynamics.
- Analysis focused on limiting and overlimiting regimes of electroconvection.
- Investigated resonant interactions, including sideband and subharmonic resonances, and the influence of wall corrugation.
Main Results:
- Identified resonant interactions between EOF and electrokinetic instability near the instability threshold, leading to amplified current.
- Observed complex interactions in overlimiting regimes, including negative sideband and positive subharmonic resonances.
- Demonstrated that wall corrugation can resonate with unstable modes and, in some cases, suppress electrokinetic instability.
Conclusions:
- The nonlinear coupling of electro-osmotic flow and electrokinetic instability significantly influences electric current enhancement.
- Resonant interactions play a critical role in both limiting and overlimiting regimes.
- Wall corrugation presents a tunable parameter that can modify or even inhibit electrokinetic instability, offering potential for controlling electroconvective phenomena.
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