We investigate the thin-double-layer electrophoretic drift of a uniformly charged dielectric particle, driven by an intense electric field comparable to the transverse Debye-layer field. Under these circumstances, solid polarization affects the leading-order electrokinetic transport in the fluid by inducing a nonuniform zeta-potential distribution. The resulting expression for the particle velocity is accordingly nonlinear in the applied field. The electrophoretic “mobility”—the ratio of this velocity and the applied field—depends upon two parameters, the first quantifying the surface-charge density, and the second constituting the product of the solid-to-liquid permittivity ratio and the scaled applied-field magnitude. At weak values of this product, solid polarization results in field-cubed deviations from Smoluchowski's velocity; at large values of it, the particle velocity is a slowly increasing function of the applied field, essentially varying with its logarithm. The transition between these two limits features a shift from zeta-potential proportionality to a charge-density proportionality. For all values of the two governing parameters solid polarization acts so as to reduce the electrophoretic velocity relative to the Smoluchowski limit.
Skip Nav Destination
Article navigation
August 2012
Research Article|
August 30 2012
Dielectric-solid polarization at strong fields: Breakdown of Smoluchowski's electrophoresis formula
Ory Schnitzer;
Ory Schnitzer
Department of Mathematics,
Technion-Israel Institute of Technology
, Technion City, Haifa, 36000, Israel
Search for other works by this author on:
Ehud Yariv
Ehud Yariv
Department of Mathematics,
Technion-Israel Institute of Technology
, Technion City, Haifa, 36000, Israel
Search for other works by this author on:
Physics of Fluids 24, 082005 (2012)
Article history
Received:
June 11 2012
Accepted:
August 15 2012
Citation
Ory Schnitzer, Ehud Yariv; Dielectric-solid polarization at strong fields: Breakdown of Smoluchowski's electrophoresis formula. Physics of Fluids 1 August 2012; 24 (8): 082005. https://doi.org/10.1063/1.4748967
Download citation file:
Sign in
Don't already have an account? Register
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Sign in via your Institution
Sign in via your InstitutionPay-Per-View Access
$40.00