Volume 19, Issue 8 (August 2019)                   Modares Mechanical Engineering 2019, 19(8): 2057-2066 | Back to browse issues page

XML Persian Abstract Print


Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:

Maleki Bagherabadi K, Sani M, Saidi M. Numerical Analysis of Some Active and Passive Electro-Kinetic Micro-Mixers by Applying Poisson-Nernst-Planck and Navier–Stokes (PNP-NSE) Equations. Modares Mechanical Engineering 2019; 19 (8) :2057-2066
URL: http://mme.modares.ac.ir/article-15-25325-en.html
1- School of Science & Engineering, Sharif University of Technology - International Campus Kish Island, Kish Island, Iran
2- School of Science & Engineering, Sharif University of Technology - International Campus Kish Island, Kish Island, Iran , msani@sharif.edu
3- Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
Abstract:   (5357 Views)
Micro-mixers are vital components of “Lab-on-a-Chip” devices. Their main functionality is the mixing of two streams with desired quality and at minimum mixing time. In this work, numerical modelings of some active and passive micro-mixers with innovative designs are reported. Increasing mixing quality and decreasing mixing time are the design objectives. Our numerical model features solving the set of non-linear and inter-coupled Poisson-Nernst-Planck-Naiver-Stokes equations (PNP-NSE) instead of using simplified models like Poisson-Boltzmann (PB). These equations describe a more realistic model of the physics involved at continuum level by incorporating diffusion, electro-migration, and convection, which are the dominant phenomena in electro-kinetic micro-mixers especially those using AC voltage electrodes. The computations are carried out using Rayan (in-house code). The traditional Poisson-Boltzmann (PB) model relies on simplifying assumptions and is proven to lose its accuracy in complex geometries and near active electrodes. On the other hand, the PB model is much less sophisticated and therefore much less computationally expensive. One of the contributions of this research is to show that in passive micro-mixers making the obstacles smaller but more numerous increases the mixing quality (for the case studied by 13%). The other major contribution of this work is the introduction of the combination of the vertical and horizontal AC electrodes. This new design creates jets normal to the direction of the mainstream which is responsible for enhancing chaotic mixing. This results in a stable mixing quality of 99% at 2.7s.
Full-Text [PDF 4560 kb]   (3302 Downloads)    
Article Type: Original Research | Subject: Marine Structures
Received: 2018/09/23 | Accepted: 2019/01/29 | Published: 2019/08/12

References
1. Chen C, Cho CC. Electrokinetically driven flow mixing utilizing chaotic electric fields. Microfluidics and Nanofluidics. 2008;5(6):785-793. [Link] [DOI:10.1007/s10404-008-0286-4]
2. Hardt S, Schönfeld F. Microfluidic technologies for miniaturized analysis systems. Switzerland: Springer; 2007. [Link] [DOI:10.1007/978-0-387-68424-6]
3. Kler PA. Modeling and simulation of microfluidic chips for analytical applications [Dissertation]. Santa Fe, Argentina: National University of the Littoral; 2010. [Link]
4. Lim CY, Lam YC. Analysis on micro-mixing enhancement through a constriction under time periodic electroosmotic flow. Microfluidics and Nanofluidics. 2012;12(1-4):127-141. [Link] [DOI:10.1007/s10404-011-0856-8]
5. Lynn NS, Henry CS, Dandy DS. Microfluidic mixing via transverse electrokinetic effects in a planar microchannel. Microfluidics and Nanofluidics. 2008;5(4):493-505. [Link] [DOI:10.1007/s10404-008-0258-8]
6. Melin J, Giménez G, Roxhed N, van der Wijngaart W, Stemme G. A fast passive and planar liquid sample micromixer. Lab on a Chip. 2004;4(3):214-219. [Link] [DOI:10.1039/B314080F]
7. Chao K, Chen B, Wu J. Numerical analysis of field-modulated electroosmotic flows in microchannels with arbitrary numbers and configurations of discrete electrodes. Biomedical Microdevices. 2010;12(6):959-66. [Link] [DOI:10.1007/s10544-010-9450-1]
8. Zhao C, Yang C. Advances in electrokinetics and their applications in micro/nano fluidics. Microfluidics and Nanofluidics. 2012;13(2):179-203. [Link] [DOI:10.1007/s10404-012-0971-1]
9. Glasgow I, Batton J, Aubry N. Electroosmotic mixing in microchannels. Lab on a Chip. 2004;4(6):558-562. [Link] [DOI:10.1039/b408875a]
10. Erickson D, Li D. Microchannel flow with patchwise and periodic surface heterogeneity. Langmuir. 2002;18(23):8949-8959. [Link] [DOI:10.1021/la025942r]
11. Cheng Y, Jiang Y, Wang W. Numerical simulation for electro-osmotic mixing under three types of periodic potentials in a T-shaped micro-mixer. Chemical Engineering and Processing-Process Intensification. 2018;127:93-102. [Link] [DOI:10.1016/j.cep.2018.03.017]
12. Shamloo A, Mirzakhanloo M, Dabirzadeh MR. Numerical simulation for efficient mixing of newtonian and non-newtonian fluids in an electro-osmotic micro-mixer. Chemical Engineering and Processing: Process Intensification. 2016;107:11-20. [Link] [DOI:10.1016/j.cep.2016.06.003]
13. Barman U, Sen AK, Mishra SC. Theoretical and numerical investigations of an electroosmotic flow micropump with interdigitated electrodes. Microsystem Technologies. 2014;20(1):157-168. [Link] [DOI:10.1007/s00542-013-1893-x]
14. Lin JL, Lee KH, Lee GB. Active micro-mixers utilizing a gradient zeta potential induced by inclined buried shielding electrodes. Journal of Micromechanics and Microengineering. 2006;16(4):757. [Link] [DOI:10.1088/0960-1317/16/4/012]
15. Chen H, Zhang Y, Mezic I, Meinhart C, Petzold L. Numerical simulation of an electroosmotic micromixer. A SME 2003 International Mechanical Engineering Congress and Exposition. Washington, DC: American Society of Mechanical Engineers; 2003. [Link] [DOI:10.1115/IMECE2003-55017]
16. Bera S, Bhattacharyya S. Effects of geometric modulation and surface potential heterogeneity on electrokinetic flow and solute transport in a microchannel. Theoretical and Computational Fluid Dynamics. 2018;32(2):201-214. [Link] [DOI:10.1007/s00162-017-0448-7]
17. Kang S, Suh YK. Numerical analysis on electroosmotic flows in a microchannel with rectangle-waved surface roughness using the Poisson-Nernst-Planck model. Microfluidics and Nanofluidics. 2009;6(4):461-477. [Link] [DOI:10.1007/s10404-008-0321-5]
18. Sani M, Saidi MS. Rayan: A polyhedral grid co-located incompressible finite volume solver (part I: basic design features). Scientia Iranica. 2010;17(6):443-455. [Link]
19. Sani M, Saidi MS. A set of particle locating algorithms not requiring face belonging to cell connectivity data. Journal of Computational Physics. 2009;228(19):7357-7367. [Link] [DOI:10.1016/j.jcp.2009.06.031]
20. Sani M, Saidi MS. A lagged implicit segregated data reconstruction procedure to treat open boundaries. Journal of Computational Physics. 2010;229(14):5418-5431. [Link] [DOI:10.1016/j.jcp.2010.04.005]
21. Nayak A. Analysis of mixing for electroosmotic flow in micro/nano channels with heterogeneous surface potential. International Journal of Heat and Mass Transfer. 2014;75:135-144. [Link] [DOI:10.1016/j.ijheatmasstransfer.2014.03.057]
22. Masliyah JH, Bhattacharjee S. Electrokinetic and colloid transport phenomena. Hoboken, New Jersey: John Wiley & Sons; 2006. [Link] [DOI:10.1002/0471799742]
23. Park HM, Lee JS, Kim TW. Comparison of the Nernst-Planck model and the Poisson-Boltzmann model for electroosmotic flows in microchannels. Journal of Colloid and Interface Science. 2007;315(2):731-739. [Link] [DOI:10.1016/j.jcis.2007.07.007]
24. Park HM, Choi YJ. Electroosmotic flow driven by oscillating zeta potentials: Comparison of the Poisson-Boltzmann model, the Debye-Hückel model and the Nernst-Planck model. International Journal of Heat and Mass Transfer. 2009;52(19-20):4279-4295. [Link] [DOI:10.1016/j.ijheatmasstransfer.2009.04.022]
25. Goullet A, Glasgow I, Aubry N. Effects of microchannel geometry on pulsed flow mixing. Mechanics Research Communications. 2006;33(5):739-746. [Link] [DOI:10.1016/j.mechrescom.2006.01.007]
26. Wang J, Wang M, Li Z. Lattice Poisson-Boltzmann simulations of electro-osmotic flows in microchannels. Journal of Colloid and Interface Science. 2006;296(2):729-736. [Link] [DOI:10.1016/j.jcis.2005.09.042]
27. Luo WJ. Transient electroosmotic flow induced by AC electric field in micro-channel with patchwise surface heterogeneities. Journal of Colloid and Interface Science. 2006;295(2):551-561. [Link] [DOI:10.1016/j.jcis.2005.09.052]

Add your comments about this article : Your username or Email:
CAPTCHA

Send email to the article author


Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.