Steric and slippage effects on mass transport by using an oscillatory electroosmotic flow of power-law fluids

Ruben Baños, José Arcos, Oscar Bautista, Federico Méndez

Research output: Contribution to journalArticlepeer-review

7 Scopus citations

Abstract

In this paper, the combined effect of the fluid rheology, finite-sized ions, and slippage toward augmenting a non-reacting solute’s mass transport due to an oscillatory electroosmotic flow (OEOF) is determined. Bikerman’s model is used to include the finite-sized ions (steric effects) in the original Poisson-Boltzmann (PB) equation. The volume fraction of ions quantifies the steric effects in the modified Poisson-Boltzmann (MPB) equation to predict the electrical potential and the ion concentration close to the charged microchannel walls. The hydrodynamics is affected by slippage, in which the slip length was used as an index for wall hydrophobicity. A conventional finite difference scheme was used to solve the momentum and species transport equations in the lubrication limit together with the MPB equation. The results suggest that the combined slippage and steric effects promote the best conditions to enhance the mass transport of species in about 90% compared with no steric effect with proper choices of the Debye length, Navier length, steric factor, Womersley number, and the tidal displacement.

Original languageEnglish
Article number539
JournalMicromachines
Volume12
Issue number5
DOIs
StatePublished - May 2021

Keywords

  • Boundary slip
  • Mass transport rate
  • Oscillatory electroosmotic flow
  • Power-law fluids
  • Steric effect

Fingerprint

Dive into the research topics of 'Steric and slippage effects on mass transport by using an oscillatory electroosmotic flow of power-law fluids'. Together they form a unique fingerprint.

Cite this