Induced-charge electroosmotic flow around dielectric particles in uniform electric field

• The induced potential of a dielectric material is dependent on the relative permittivity.
• The ICEOF does not affect the transportation of a single particle in a microchannel.
• Two closely located dielectric particles appeal or repel each other due to the ICEOF.

The current research of induced-charge electroosmotic flow (ICEOF) is mostly confined to systems with ideally or fully polarizable surfaces (e.g., metal). However, most materials in nature have various degrees of polarizability, which directly affects the induced charges and subsequently the induced-charge electroosmotic flow. This paper studied the effect of the polarizability of the materials on the ICEOF. An analytical expression of the induced potential on the surface of a dielectric particle in a uniform electrical field was derived. Three-dimensional transient numerical simulations of the ICEOF and the motion of dielectric particles were performed to study the effect of the polarizability. Simulation results show that the transportation of the dielectric particle in a microchannel is not affected by the polarizability of the particle; however, the interaction of two dielectric particles is sensitive to the polarizability of the particles.

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