Mixing Enhancement by Induced-Charge Electrokinetic Flow

The induced-charge electrokinetic flow (ICEKF) in a rectangular micorchannel with conducting hurdles embedded in the middle is investigated in this paper. A correction method is suggested to numerically estimate the induced zeta potential on the conducting surface. Two-dimensional pressure-linked Navior-Stokes equation is used to model the flow field in the channel. The numerical results show flow circulations generated from the induced non-uniform zeta potential distribution along the conducting hurdle surfaces. It is demonstrated numerically that the local flow circulations provide effective means to enhance the flow mixing between different solutions; the degree of enhancement depends on the hurdle geometries and hurdle numbers. The mixing using ICEKF described in this paper can be used in various microfluidics and lab-on-a-chip applications.