NUMERICAL ANALYSIS OF ALTERNATIVE CURRENT ELECTROOSMOSIS MICROPUMP (ACEO) WITH PLANAR-INCLINED MICROELECTRODES

Recent numerical and experimental studies have investigated the increase in efficiency of microfluidic ac electroosmosis (ACEO) pumps by introducing nonplanar geometries with raised steps on the electrodes. The current study demonstrates dramatic improvements in fluid velocity and frequency range over alternative current electroosmosis micropumps by exploiting two-dimensional (2D) planar-inclined microelectrode. The step microelectrodes are known to faster performance than planar asymmetric microelectrodes. So, the geometry of microelectrode is very effective to the flow pumping of alternative current electroosmosis micropumps. The inclined microelectrode is introduced to numerical method with negative slope in present work. The numerical simulations of fluid flow are done by solving electric and Navier-Stokes equations by linear model. Potential distribution in the computing space is obtained with solving Laplace's equation In the linear model and slip velocity as flow boundary condition is resulted by this distribution. Different geometries (the electrode height and width electrode), frequencies and voltages cause impressive changes to the performance of alternative current electroosmosis micropumps. The results show that the pumping flow rate is increased considerably in micropumps with planar-inclined microelectrode that the flow rate is about 20% more than the step electrode.