Commenced in January 2007
Paper Count: 31532
Influence of a Pulsatile Electroosmotic Flow on the Dispersivity of a Non-Reactive Solute through a Microcapillary
Abstract:The influence of a pulsatile electroosmotic flow (PEOF) at the rate of spread, or dispersivity, for a non-reactive solute released in a microcapillary with slippage at the boundary wall (modeled by the Navier-slip condition) is theoretically analyzed. Based on the flow velocity field developed under such conditions, the present study implements an analytical scheme of scaling known as the Theory of Homogenization, in order to obtain a mathematical expression for the dispersivity, valid at a large time scale where the initial transients have vanished and the solute spreads under the Taylor dispersion influence. Our results show the dispersivity is a function of a slip coefficient, the amplitude of the imposed electric field, the Debye length and the angular Reynolds number, highlighting the importance of the latter as an enhancement/detrimental factor on the dispersivity, which allows to promote the PEOF as a strong candidate for chemical species separation at lab-on-a-chip devices.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1340414Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 418
 Stone H. A, Stroock A. D., and Ajdari A. Engineering flows in small devices: microfluidics toward a lab-on-a-chip. Annu. Rev. Fluid Mech., 36:381–411, 2004.
 Mei C. C. and Vernescu B. Homogenization methods for multiscale mechanics. World scientific, 2010.
 Tretheway D. C. and Meinhart C. D. Apparent fluid slip at hydrophobic microchannel walls. Phys. Fluids, 14:9–12, 2002.
 J. Chakraborty, S. Ray, and S. Chakraborty. Role of streaming potential on pulsating mass flow rate control in combined electroosmotic and pressure-driven microfluidic devices. Electrophoresis, 33:419–425, 2012.
 Subhra Datta, , and Sandip Ghosal. Characterizing dispersion in microfluidic channels. Lab Chip, 9:2537–2550, 2009.
 Lauga E., Brenner M., and Stone H. Microfluidics: The No-slip Boundary Condition. Springer, Berlin Heidelberg, 2007.
 Huang H. F. and Lai C. L. Enhancement of mass transport and separation of species by oscillatory electroosmotic flows. Proc. R. Soc. A., 462:2017–2038, 2006.
 Probstein R. F. Physicochemical hydrodynamics: an introduction. John Wiley and Sons, 1994.
 Green N. G., Ramos A., Gonzalez A., Morgan H., and Castellanos A. Fluid flow induced by nonuniform ac electric fields in electrolytes on microelectrodes. i. experimental measurements. Phys. Rev., 61:4011–4018, 2000.
 Leal L. G. Advanced transport phenomena. Cambridge University Press, 2007.
 Rojas G., Arcos J., Peralta M., M´endez F., and Bautista O. Pulsatile electroosmotic flow in a microcapillary with the slip boundary condition. Colloid Surf. A-Physicochem. Eng. Asp, 513:57–65, 2017.
 Sandip Ghosal. Electrokinetic flow and dispersion in capillary electrophoresis. Annu. Rev. Fluid Mech., 38:309–338, 2006.
 Oddy M. H., Santiago J. G., and Mikkelsen J. C. Electrokinetic instability micromixing. Anal. Chem., 73:5822–5832, 2001.
 Taylor G. I. Dispersion of soluble matter in solvent flowing slowly through a tube. Proc. R. Society A., 219:186–203, 1953.
 A. Mat´ıas, S. S´anchez, F. M´endez, and O. Bautista. Influence of slip wall effect on a non-isothermal electro-osmotic flow of a viscoelastic fluid. Int. J. Therm. Sci., 98:352–363, 2015.
 C. C. Mei, J. L. Auriault, and C. O. Ng. Some applications of the homogenization theory. Advances in Applied Mechanics, 32:277–348, 1996.
 C. O. Ng. Dispersion in steady and oscillatory flows through a tube with reversible and irreversible wall reactions. Proc. R. Soc. A, 462:481–515, 2006.
 Ng C. O. and Zhou Q. Dispersion due to electroosmotic flow in a circular microchannel with slowly varying wall potential and hydrodynamic slippage. Phys. Fluids., 24:112002, 2012.
 Suvadip Paul and Chiu-On Ng. Dispersion in electroosmotic flow generated by oscillatory electric field interacting with oscillatory wall potentials. Microfluid Nanofluid, 12:237–256, 2012.
 M. Peralta, J. Arcos, F. M´endez, and O Bautista. Oscillatory electroosmotic flow in a parallel- plate microchannel under asymmetric zeta potentials. Fluid Dyn. Res., 49:035514, 2017.
 Zhou Q. and Ng C. O. Electro-osmotic dispersion in a circular tube with slip-stick striped wall qe11. Fluid Dyn. Res., 47:015502, 2015.
 Chakraborty S. and Ray S. Mass flow-rate control through time periodic electro-osmotic flows in circular microchannels. Phys. Fluids., 20(083602):1–11, 2008.