Enhancement of flow mixing in micro and nano channels

Nayak, Ameeya Kumar

ANZIAM Journal, Tome 55 (2014), / Harvested from Australian Mathematical Society

Résumé

The aim is to increase the mixing potential of ion species in micro and nano channels with heterogeneous surface potential. We discuss the generation of vortical flow, due to the presence of wall heterogeneity at different locations in the channel. The flow characteristics are obtained by numerical solution of the Poisson equation, the Nernst--Planck equation, and the Navier--Stokes equation, simultaneously. A numerical method based on the pressure correction iterative algorithm is adopted to compute the flow field and mole fraction of the ions. The strong recirculation vortices which appear above the heterogeneities generate a strong pressure gradient which increases mixing performance. References F. Tian, B. Li and D. Y. Kwok, Tradeoff between mixing and transport for EOF in hetero. microchannels with nonuniform surface potentials. Langmuir 21:1126–1131, 2005. doi:10.1021/la048203e R. H. Liu, M. A. Stremler, K. V. Sharp, M. G. Olsen, J. G. Santiago, R. J. Adrian, H. Aref and D. J. Beebe, Passive mixing in a three dimensional serpentine microchannel. J. Microelectromech. S. 9:190–197, 2000. doi:10.1109/84.846699 Z. M. Wu, Z. J. Zhao, J. X. Yang, L. P. Liu and X. L. Yang, Freq.-modulation-type MI sensor with nanocrystalline ribbon core. Sensor. Actuat. A:Phys. 121:430–433, 2005. doi:10.1016/j.sna.2005.03.019 S. Bhattacharyya and A. K. Nayak, Combined Effect of Surface Roughness and Heterogeneity of Wall Potential on Electroosmosis in Microfluidic/Nanofuidic Channels. J. Fluids Eng. 132:041103, 2010. doi:10.1115/1.4001308 A. Ajdari, Electro-Osmosis on Inhomogeneously Charged Surfaces. Phy. Rev. Lett. 75:755–758, 1995. doi:10.1103/PhysRevLett.75.755 D. Erickson and D. Li Influence of surface heterogeneity on electrokinetically driven microfluidic mixing. Langmuir 18:1883–1892, 2002. doi:10.1021/la015646z L. M. Fu , J. Y. Lin and R. J. Yang, Analysis of electroosmtoic flow with step change in zeta potential. J. Colloid. Interf. Sci. 258:266–275, 2003. doi:10.1016/S0021-9797(02)00078-4 H. Watzig, S. Kaupp and M. Graf, Inner surface properties of capillaries for electrophoresis. Trac-Trend. Anal. Chem. 22:588–604, 2003. doi:10.1016/S0165-9936(03)01102-6 Z. Zheng and D. Hansford, and A. T. Conlisk, Effect of multivalent ions on EOF in micro- and nanochannels. Electrophoresis 24:3006–3017, 2003. doi:10.1002/elps.200305561 J. Wang, M. Wang and Z. Li, Lattice Poisson–Boltzmann Simulations of Electro-Osmotic Flows in Microchannels. J. Colloid. Interf. Sci. 296:729–736, 2006. doi:10.1016/j.jcis.2005.09.042 A. K. Nayak, An Analysis of Steady/Unsteady Electroosmotic flows Through Charged cylindrical nano channel. Theor. Comp. Fluid Dyn. 27:885–902, 2013. doi:10.1007/s00162-013-0295-0

Détail

Publié le : 2014-01-01
DOI : https://doi.org/10.21914/anziamj.v55i0.7814