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

TL;DR

This paper investigates how asymmetrical micro electrode surface topography influences AC electroosmosis flow rate, introducing a modified EDL model that aligns well with experimental data.

Contribution

It presents a novel equivalent EDL model incorporating electrode surface roughness to accurately predict ACEO flow rates.

Findings

Surface roughness significantly affects ACEO flow rate.

The modified EDL model matches experimental results closely.

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.