Electrokinetic flow near an undulated, charged surface

In this study, using the iterative finite difference method, the effect of an irregular condition at boundary, the surface undulation, in a charged surface system on the two dimensional electrokinetic flow near the surface is analyzed. The results reveal that, for the electrokinetic flow, the undulation of charged surface may have two major effects: one is that it changes the flow pattern of electrolyte solution, especially in the region close to the undulated surface; the other is that, due to the increase of effective surface area, the magnitude of velocity field may be increased considerably. In addition, when either the amplitude of undulation is increased, or the period of undulation is decreased, both the maximum velocity and the tangential flow rate will be raised to an extent. This is important for applications, for example, the electrophoresis of a biological cell, the electroosmosis of electrolyte solution in a micro-channel, etc.