Motivated by the growing interest in electroosmotic flows (EOFs) as a reliable no moving parts strategy to control fluid motion in various micro fluidics, two-dimensional (2D) steady-state EOFs in the presence of a charged mid-plate have been numerically investigated. A variation of lattice Boltzmann models is used to recover all governing equations, where the Nernst–Planck equation is employed to model the internal electrical field. Results are validated by comparing the velocity profiles in the 2D uniform EOFs against their analytical solutions. The numerical results show that the velocity pro¯le and volumetric °ow rate are strongly in°fluenced by the ratio of the electrical double layer (EDL) thickness to the channel height. In addition, the effects of positioning and thickness of the charged mid-plate on the electric field distribution, velocity profile and flow rate are examined in detail.

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