In this paper, a numerical study is performed on an induced-charge electrokinetic micromixer. The electrically conductive plates are installed inside the micromixer to induce vortices that improve the mixing index of the system. A comprehensive geometrical study is performed on this micromixer and the effects of various parameters are investigated. These parameters include the mounting, length, orientation, position, arrangement and number of the conductive plates, and the intensity of the external electric field. To benchmark the accuracy of the numerical model, the simulated results are compared and agree well with existing experimental and numerical data in the literature. The results show that a mixing efficiency of 99.6% can be achieved by placing two 5° angle conductive plates near the upper and lower walls and one 5° angle conductive plate at the center of the micromixer. It is also observed that the mixing performance increases with increasing conductive plate length. The mixing efficiency can be improved from 67.2% to 94.3% by increasing the plate angle from 0° to 40°. Combining these optimizations, close to 100% mixing efficiency can be achieved by placing three staggered and tilted conductive plates at an angle of 5°.

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