Abstract <p>Electrokinetic flow is a special category of fluid flow driven by or subjected to electric body forces, which are regulated by a series of determinants including the strength and structure of the electric field, frequency, electric permittivity/conductivity, and fluid viscosity, among others. Efficient and rapid micromixing of fluids, which constitutes one of the fundamental operations in microfluidic devices, can enable a wide range of applications, from biochemical reactions to medical diagnostics and beyond. In the case of microfluids, successful micromixing becomes challenging to obtain in pure linear microchannels or in the absence of external field perturbations due to the prevalence of laminar flow conditions in such systems. In this work, an electroosmosis-based micromixer has been designed to combine two different fluids. To enhance the efficiency of this mixing system, a sinusoidal electric potential is imposed systematically across the electrodes with a peak value of 0.1 V and an operating frequency of 8 Hz. In order to enhance the efficiency of the micromixer, rectangular-shaped obstacles have been added along the micromixer sidewalls. Based on this structure, the results of the simulation demonstrate that the micromixer attains an excellent efficiency of the order of 96%, thus emphasizing its immense potential for useful applications in a wide range of disciplines, with special reference to microfluidics, biochemistry, and biomedical sciences.</p>