交流电场作用下微电极表面电渗流流速的计算

为解决微流体在交流电场作用下电极表面电渗流的流速计算方法,在电极极化产生双电层的基础上,建立了交流电渗等效电路模型,通过对双电层容抗和溶液电阻的计算,得出了微电极表面交流电渗流流速的计算公式,并对各点交流电渗流速与频率的关系进行了分析.结果表明,电极参数为宽80μm,长2 mm,电极间距20μm的对称电极交流电渗,在电极表面上的各点电渗流流速与输入信号频率对数呈正态分布状态.研究结果为交流电渗驱动微流体提供了理论参考依据.

Velocity calculation of the electro-osmotic flow on the surface of microelectrode caused by AC electric field

To calculate the velocity of pumping microflows on the surface of electrode under the effect of AC electric field,an equivalent circuit model was presented on the basis of electric double layer caused by the polarization effects at the electrodes.By calculating the impedance of electric double layer capacitance and resistance of solution,the formula for calculating the velocity of AC electroosmosis flow on the surface of electrode was developed.The relationship between velocity and frequency was analyzed.The results show that the velocity of electro osmotic flow on the surface and the logarithm of frequency exhibit a normal distribution with electrode parameters as follows: width of 80 μm,length of 2 mm and the distance between electrodes of 20 μm.This study offers insights for the research of AC electroosmotic pumping microflow.