Effects of Ion Concentration on Electroosmotic Flow and Micromixing in Microchannels

YANG Da-yong; WANG Yang

doi:10.3879/j.issn.1000-0887.2015.09.009

Volume 36 Issue 9

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YANG Da-yong, WANG Yang. Effects of Ion Concentration on Electroosmotic Flow and Micromixing in Microchannels[J]. Applied Mathematics and Mechanics, 2015, 36(9): 981-989. doi: 10.3879/j.issn.1000-0887.2015.09.009

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Effects of Ion Concentration on Electroosmotic Flow and Micromixing in Microchannels

doi: 10.3879/j.issn.1000-0887.2015.09.009

Information Engineering School of Nanchang University, Nanchang 330031, P.R.China

Funds: The National Natural Science Foundation of China(11302095)

Received Date: 2015-05-15
Rev Recd Date: 2015-07-12
Publish Date: 2015-09-15

Abstract

Abstract

Electroosmotic flow is widely used to transport and mix fluids in microfluidic chips. A variable model for the ion concentration gradient effects on the electroosmotic flow and micromixing in microchannels was presented. The effects were investigated numerically with the finite element method. The impacts of the zeta potential and the dielectric constant on the flow field and concentration field were also analyzed. The micromixing efficiency in the microchannel was evaluated quantitatively. The results show that the flow field is inhomogeneous, and the distribution of the ion concentration will be asymmetric in the microchannel while the zeta potential and the dielectric constant vary with the ion concentration. When the concentration of the electrolyte solution is approximate to 1 mol/L, the solution essentially couldn't be driven into the microchannel. The micromixing efficiency decreases with the ion concentration difference between the electrolyte solutions, and the larger the difference is, the shorter the distance is needed to reach perfect mixing.
- electroosmotic flow,
- ion concentration,
- dielectric constant,
- zeta potential

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References(19)

References

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