In order to study on effect of electroosmotic flow(EOF)in U-type capillary electrode on measurement result of the surface Zeta potential of micro/nano-particles,based on the U-type capillary electrode,the EOF initiation mechanism and its inhibition mechanism by high frequency alternating voltage are analyzed by numerical simulation.Results show that when the DC voltage is applied by the capillary electrode,the EOF of wall surface generates backflow under the pressure gradient of the tube wall surface.Its startup time is millisecond(ms).When applying high frequency alternating voltage,high frequency alternating electric field hindereds the launch of EOF and local oscillatory flow is generated at the wall surface.As the frequency increases,the inhibition of capillary EOF is more intense.Compared with other waveform voltages,triangle wave has better suppression effect on EOF,and the amplitude range of local oscillation current is smaller.This research has reference significance for particle Zeta potential detection and precise control of microfluidic electric flow.
关键词
封闭毛细管/电渗流/交变电场
Key words
closed-end capillary/electroosmotic flow(EOF)/alternative electric field
维普
万方数据