关键词: 电渗流, 矩形微流道, 数值模拟, 影响因素, 有限控制容积法

Abstract: Aiming at the design parameter optimization problem of the electroosmotic pumping, the mathematic model of electroosmotic flow is made. The coupling equations governing the electric double layer (EDL) field and the velocity field in the cross-section of rectangular microchannels are numerically solved by employing a finite control volume scheme. The de-pendence of the potential, velocity and volumetric flowrate on the aspect ratio, hydraulic diameter, liquid properties and the applied electrical field is analyzed. And the fitting polynomials of the relationships between the volumetric flow, average ve-locity and influence factors are presented. The numerical simu-lation results show that the volumetric flowrate decreases as the aspect ratio increases. When the aspect ratio approaches 1, the volumetric flowrate is minimum. The volumetric flowrate in-creased with the square of hydraulic diameter. The average velocity is dependent on the ionic concentration and the applied electrical field strength. However, the aspect ratio and hydraulic diameter have little impact on the average velocity.

Key words: Electroosmotic flow, Finite control volume scheme Rectangular microchannel, Influence factors, Numerical simulation