Issue
Korean Journal of Chemical Engineering,
Vol.29, No.2, 154-161, 2012
Electrokinetic effects on fluid flow and particle transport
The effect of counter-electroosmotic flow on the particle trajectories, the particle equilibrium position, and the critical flux was for the first time evaluated in normal flow filtration using numerical solution of the two-dimensional coupled Navier-Stokes, Nernst-Plank, and Poisson equations for a slit pore having a converging entrance. It was shown that the numerical results for the velocity profiles, ion concentrations, and induced streaming potential were in good agreement with analytical expressions obtained for a simple slit shaped. Numerical simulations for particle transport were performed at both constant pressure and constant filtration velocity in the presence of counter-electroosmosis. A significant shift in the particle trajectory and final equilibrium location were shown at constant pressure due to the reduction in the filtrate flux associated with the counter-electroosmotic flow arising from the induced streaming potential. However, simulations conducted at a constant filtration velocity showed only a very small effect of counterelectroosmosis, with the equilibrium position varying by less than 5% for calculations performed in the presence/absence of counter-electroosmosis. This result stems from a very small distortion in the velocity profile in the region above the pore due to the greater contribution from counter-electroosmosis in the region immediately adjacent to the pore wall. This paper will provide a useful framework to evaluate particle transport in the presence of electrokinetic phenomena.
[References]
  1. Ajdari A, Phys. Rev. E., 53, 4996, 1996
  2. Herr AE, Molho JI, Santiago JG, Mungal MG, Kenny TW, Garguilo MG, Anal. Chem., 72, 1053, 2000
  3. Ghosal S, J.Fluid Mech., 459, 103, 2002
  4. Yao SH, Hertzog DE, Zeng SL, Mikkelsen JC, Santiago JG, J. Colloid Interface Sci., 268(1), 143, 2003
  5. Yao SH, Santiago JG, J. Colloid Interface Sci., 268(1), 133, 2003
  6. Brotherton CM, Davis RH, J. Colloid Interface Sci., 270(1), 242, 2004
  7. Hlushkou D, Kandhai D, Tallarek U, Int. J. Numerical Methods in Fluids., 46, 507, 2004
  8. Rice CL, Whitehead R, J. Phys. Chem., 69, 4017, 1965
  9. Anderson JL, Koh WH, J. Colloid Interface Sci., 59, 149, 1977
  10. Saksena S, Zydney AL, Biotechnol. Bioeng., 43(10), 960, 1994
  11. Bowen WR, Cao XW, J. Membr. Sci., 140(2), 267, 1998
  12. Newman JS, Electrochemical systems. Englewood Cliffs, NJ, Prentice Hall, 1991
  13. Kim MM, Zydney AL, J. Colloid Interface Sci., 269(2), 425, 2004
  14. Kim MM, Zydney AL, Chem. Eng. Sci., 60(15), 4073, 2005
  15. Probstein RF, Physicochemical Hydrodynamic An Introduction, Stoneham, MA, Butterworth Publisher, 1989
  16. Pujar NS, Zydney AL, Ind. Eng. Chem. Res., 33(10), 2473, 1994