Advances in the Standards & Applied Sciences

Advances in the Standards & Applied Sciences

A comparative numerical simulation of the electrokinetic micromixers

Document Type : Original Article

Authors
1 Department of biomechanics Science and Research Branch Islamic Azad University
2 Department of Biomedical Engineering, Islamic Azad University, Central Tehran Branch, Tehran, Iran
3 Department of Mechanical Engineering, Islamic Azad University, Central Tehran Branch, Tehran, Iran
4 Biomedical Engineering Research Group, Research Center of Technology and Engineering, Standard Research Institute, Karaj, Iran
Abstract
Micromixing has a practical application in analyzing of many biochemical and biologicals detection devices of lab-on-a-chip (LOC). The conventional static micromixers require the channel with more lengths and also require times to reach to complete mixing owing to its dependence on transverse diffusion. However, in the electrokinetic micromixers, as the surface properties of the microchannel run the electro-osmotic flow characteristics, surface heterogeneity (non-uniform zeta potentials) can be seen to make vortices or specific flow structures for better mixing performance. This study aims to use computational fluid dynamics (CFD) to numerically compare the concentration rate of the various electrokinetic micromixers in in the presence of the electric conductor. The results revealed that the off-center microchannel design in a micromixer can augment the rate of concentration. In addition, circular microchannel design showed better mixing compared to the triangular and square designs. These results are useful not only for understanding of the profiles of concentration in the electrokinetic micromixers, but also for providing a comprehensive information on the design of the microchannels, which may result in better mixture in the fluids
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