title: Electrohydrodynamics of binary electrolytes driven by modulated surface potentials.
abstract: We study the electrohydrodynamics of the Debye screening layer that arises in an aqueous binary solution near a planar insulating wall when applying a spatially modulated ac voltage. Combining this with first order perturbation theory we establish the governing equations for the full nonequilibrium problem and obtain analytic solutions in the bulk for the pressure and velocity fields of the electrolyte and for the electric potential. We find good agreement between the numerics of the full problem and the analytics of the linear theory. Our work provides the theoretical foundations of circuit models discussed in the literature. The nonequilibrium approach also reveals unexpected high-frequency dynamics not predicted by circuit models.
authors.affiliation: MIC-Department of Micro and Nanotechnology, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark.
authors.forename: Niels Asger
authors.initials: NA
authors.lastname: Mortensen
authors.forename: Laurits Højgaard
authors.initials: LH
authors.lastname: Olesen
authors.forename: Lionel
authors.initials: L
authors.lastname: Belmon
authors.forename: Henrik
authors.initials: H
authors.lastname: Bruus