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Updated: Feb 2, 2026

Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow
Published on: February 27, 2016
Quantification of Vortex Generation Due to Non-Equilibrium Electrokinetics at the Micro/Nanochannel Interface:
Seung Jun Lee1, Kilsung Kwon2, Tae-Joon Jeon3
1Department of Mechanical Engineering, Sogang University, Seoul 04107, Korea. seungjun@illinois.edu.
Abstract:
We describe a quantitative study of vortex generation due to non-equilibrium electrokinetics near a micro/nanochannel interface. The microfluidic device is comprised of a microchannel with a set of nanochannels. These perm-selective nanochannels induce flow instability and thereby produce strong vortex generation. We performed tracking visualization of fluorescent microparticles to obtain velocity fields. Particle tracking enables the calculation of an averaged velocity field and the velocity fluctuations. We characterized the effect of applied voltages and electrolyte concentrations on vortex formation. The experimental results show that an increasing voltage or decreasing concentration results in a larger vortex region and a strong velocity fluctuation. We calculate the normalized velocity fluctuation-whose meaning is comparable to turbulent intensity-and we found that it is as high as 0.12. This value is indicative of very efficient mixing, albeit with a small Reynolds number.
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