一种基于诱导电渗流的微型换向阀

A Novel Miniature Directional Valve Based on The Induced Charge Electroosmosis Flow

设计分析一种基于诱导电渗流的微型换向阀。在入口通道和出口通道的壁面拐角处布设一定尺寸的金属板,当通道两端施加一定的电压后,金属壁面产生诱导电渗流,形成两个旋转方向相反的涡流,当电压增大到一定值时,在两个涡流的共同作用下,流体会全部从另外一个出口流出。数值模拟研究表明:要获得完全的流向转换,当入口通道和出口通道金属壁面尺寸相同时,所需外加电压随金属壁面尺寸的增大而减小;当出口通道金属壁面尺寸一定时,所需外加电压随入口通道金属壁面尺寸的增大而减小;当入口通道金属壁面尺寸一定时,所需外加电压随出口通道金属壁面尺寸的增大先减小后增大;当入口通道和出口通道金属壁面尺寸一定时,所需外加电压随非金属壁面固有zeta电势绝对值的减小而减小。与传统微阀相比,该微阀不需要任何机械部件,只需在通道拐角处布置一定尺寸的金属板就可实现流向转换,可方便地布设在各种微通道内,具有较好的应用前景。

This paper reports a novel miniature directional valve based on the induced charge electroosmosis flow.A piece of metal plate is placed on the corner of the inlet channel and outlet channel. Two vortexes with opposite rotational direction will be formed on metal plate surface when an electrical field is applied across the channel. When the voltage increases to a certain value,the fluid will flow out from another outlet channel completely under the combined effect of two vortexes. Numerical simulation study shows that to obtain the complete flow direction conversion,when the metal plate size of the inlet channel and outlet channel is same,the required voltage will decrease with the increase of the metal plate size,when the metal plate size of the outlet channel is certain,the required voltage will decrease with the increase of the metal plate size of the inlet channel; when the metal plate size of the inlet channel is certain,the required voltage will decrease first and then increase with the increase of the metal plate size of the outlet channel; when the metal plate size of the inlet channel and outlet channel is certain,the required voltage will decrease with the decrease of the absolute value of the non-metallic wall zeta potential. Compared with the traditional microvalves,the micro-valve designed in this paper does not require any mechanical parts,but only needs a certain size metal plate on the corner of the channel and the complete flow direction conversion can be achieved. This kind microvalve can be easily deployed in various micro channels and has better application prospect.