Investigation of Electro-Osmotic Micro-Pumps Using Electrical Field Gradient and Asymmetric Micro-Electrodes: Numerical Modeling and Experimental Validation

Document Type : Research Article

Authors

1 SUT

2 Department of Mechanical Engineering, Shahrood University of Technology, Shahrood, Iran.

Abstract

In the present study, in order to fabricate AC electroosmotic micropumps, the improvement of geometrical parameters of the 3D electrode, such as width, height, and location of 3D steps on the base electrodes in one pair, the base electrodes size (symmetric or asymmetric), electrodes gap, and also electrical characteristics including voltage and frequency have been investigated. Also, the fluid flow (KCl) in the channel was analyzed. The governing equations of fluid flow and electrical domain have been solved using the finite element method to investigate the effect of electrode geometry on slip velocity, which affects the fluid flow. In order to validate our numerical simulation, this chip is fabricated by photolithography method such as deposition of platinum electrodes, creating 3D steps on the base electrodes using a polymer, and fabrication of a microchannel. Finally, Our results indicate that an optimal design results in a pump with the width (50 µm) and steps height (5 µm) of each electrode and their displacement (30 µm) are capable of generating a high velocity, flow rate, and pressure around 1.77 mm/s, 14.9 ml/min and 74.6 Pa, respectively at a given voltage (2.5 V) and frequency (1 kHz), which qualitatively matches the trend observed in the experiment. This design provides an improvement in electroosmotic pumping.

Keywords

Main Subjects

References

[1] H. Morgan, N.G. Green, AC Electrokinetics: Colloids and Nanoparticles, Research Studies Press, 2003.
[2] P.S. Dittrich, K. Tachikawa, A. Manz, Micro Total Analysis Systems. Latest Advancements and Trends, Analytical Chemistry, 78 (2006) 3887-3908.
[3] L. Jiang, J. Mikkelsen, J.-m. Koo, D. Huber, S. Yao, L. Zhang, P. Zhou, J.G. Maveety, R. Prasher, J.G. Santiago, T.W. Kenny, K.E. Goodson, Closed-Loop Electroosmotic Microchannel Cooling System for VLSI Circuits, IEEE Transactions on components and pachaging technologies, 25 (2002) 347-355.
[4] C.D. Meinhart, H. Zhang, The Flow Structure Inside a Microfabricated Inkjet Printhead, microelectromechanical systems, 9 (2000) 67-75.
[5] P.C.H. Li, D.J. Harrison, Transport , Manipulation , and Reaction of Biological Cells On-Chip Using Electrokinetic Effects, Analytical Chemistry, 69 (1997) 1564-1568.
[6] D.J. Laser, J.G. Santiago, A review of micropumps, Micromechanics and microengineering, 35 (2004) 35-64.
[7] J.P. Urbanski, T. Thorsen, J.A. Levitan, M.Z. Bazant, Fast ac electro-osmotic micropumps with nonplanar electrodes, Appl. Phys. Lett, 89 (2006) 143508.
[8] A. Ajdari, Pumping liquids using asymmetric electrode arrays, Phys Rev E, 61 (2000) 45-48.
[9] P. Cervenka, T. Jindra, M. Pˇ, D. Šnita, Mathematical Modeling of Traveling Wave Micropumps : Analysis of Energy Transformation, IEEE Transactions on industry applications, 49 (2013) 685-690.
[10] P.-w. Yen, S.-c. Lin, Y.-c. Huang, Y.-j. Huang, Y.-c. Tung, A Low-Power CMOS Microfluidic Pump Based on Travelling-Wave Electroosmosis for Diluted Serum Pumping, Scientific Reports, 9 (2019) 1-8.
[11] K. Yoshida, T. Sato, S.I. Eom, J.-w. Kim, S. Yokota, A Study on an AC Electroosmotic Micropump Using a Square Pole − Slit Electrode Array, Sensors & Actuators: A. Physical, 265 (2017) 1-43.
[12] X. Gao, Y.X. Li, Ultra-fast AC electro-osmotic micropump with arrays of asymmetric ring electrode pairs in 3D cylindrical microchannel, Applied physics, 123 (2018) 164-301.
[13] N. Islam., J. Reyna., Bi-directional flow induced by an AC electroosmotic micropump with DC voltage bias, Electrophoresis, 33 (2012) 1191-1197.
[14] D. Lastochkin, R. Zhou, P. Wang, Y. Ben, H.-c. Chang, Electrokinetic micropump and micromixer design based on ac faradaic polarization, Applied physics, 96 (2004) 1730-1732.
[15] H.A. Rouabah, B.Y. Park, R.B. Zaouk, H. Morgan, M.J. Madou, N.G. Green, Design and fabrication of an ac-electro-osmosis micropump with 3D high-aspect-ratio electrodes using only SU-8, Micromechanics and microoengineering, 21 (2011) 1-9.
[16] X. Guo, K. Xie, R.J. Campbell, Y. Lai, A study on three-dimensional electrode arrays fabricated by PolyMUMPs Ò for AC electro-osmotic pumping, Microelectronic Engineering, 88 (2011) 3113-3118.
[17] M. Badran., Modeling and simulation of a low voltage electroosmotic micropump for non-newtonian fluids, in:  22nd International conference on thermal, mechanical and multi-physics simulation and experiments in microelectronics and microsystems (EuroSimE), 2021, pp. 1-7.
[18] Y. Okamoto., H. Ryoson., K. Fujimoto., T. Ohba., Y. Mita., On-chip CMOS-MEMS-based electroosmotic flow micropump integrated with high-voltage generator, Microelectromechanical system, 29 (2020) 86-94.
[19] M.Z. Bazant, Y. Ben, Theoretical prediction of fast 3D AC electro-osmotic pumps, Lab Chip, 6 (2006) 1455–1461.
[20] J.P. Urbanski., J.A. Levitan., D.N. Burch., T. Thorsen., M.Z. Bazant., The effect of step height on the performance of three-dimensional ac electro-osmotic microfluidic pumps, Colloid and Interface Science, 309 (2007) 332-341.
[21] A. Ramos., H. Morgan., N.G. Green., J. A. Castellanos, AC Electric-Field-Induced Fluid Flow in Microelectrodes, Colloid and Interface Science, 217(2) (1999) 420-422.
[22] A.B.D. Brown, C.G. Smith, A.R. Rennie, Pumping of water with ac electric fields applied to asymmetric pairs of microelectrodes, Physical review E, 63 (2000) 016305.
[23] A. Ramos, A. Gonzalez, A. Castellanos, N.G. Green, H. Morgan, Pumping of liquids with ac voltages applied to asymmetric pairs of microelectrodes, Phys. Rev. E, 67 (2003) 056302.
[24] H. Morgan, A. Castellanos, Fluid flow induced by nonuniform ac electric fields in electrolytes on microelectrodes . I . Experimental measurements, Physical review E, 61 (2000) 4011.
[25] Comsol, Introduction to the Optimization Module, 2018.
[26] C.-c. Huang, Z. Bazant, T. Thorsen, Ultrafast high-pressure AC electro-osmotic pumps for portable biomedical microfluidics, Royal Society of Chemistry, 10 (2010) 80-85.
[27] D.H. Yoon, H. Sato, A. Nakahara, T. Sekiguchi, S. Konishi, S. Shoji, Development of an electrohydrodynamic ion-drag micropump using three-dimensional carbon micromesh electrodes, Micromechanics and Microengineering, 24 (2014) 1-6.
[28] B.J. Kim, S.-h. Lee, S. Rezazadeh, H.J. Sung, Simulation of an ac electro-osmotic pump with step microelectrodes, Physical review E, 83 (2011) 056302-056307.
[29] X. Guo, Fabrication and study of AC electro-osmotic, Queen’s University, 2013.
Amirkabir Journal of Mechanical Engineering
Volume 54, Issue 1
April 2022
Pages 101-122

Files

Share

How to cite

Statistics