Effects of Asymmetrical Micro Electrode Surface Topography to AC Electroosmosis flow Rate

Abstract

AC Electroosmosis (ACEO) has many advantages such as low power consumption, non-moving parts, and easy to integrate etc., so it is widely used for low concentration microfluid manipulation in low frequency range. Classical ACEO theory assumes that electric double layer (EDL) is the main cause of electric field induced flow, and gives electric-flow field coupling equations for ACEO flow rate. But the calculation data usually are tens times faster than the experimental velocities. In this paper, electrode surface topography is included to solve ACEO flow rate. With electrode surface roughness as the characteristic parameter, equivalent EDL model is set up to modify the classical EDL model. The relationship between flow rate and electrode surface roughness is studied. Experiment results agree with the simulation very well, proving the feasibility of equivalent EDL model.