The paper presents numerical simulations of electrokinetic instabilities induced in a microchamber in the presence of a fluctuating electric field for enhanced mixing. The geometry and conditions are similar to the experimental work of Oddy et al. [1]. Through dimensional analysis and numerical experiments it is found that there is an optimal choice of non-dimensional frequency and driving potential which leads to the best mixing characteristics. This is given by the relationship Reeof /f* < 5 and the condition that f* =O(10). It is also shown that a modified chamber geometry with strategically placed microbaffles leads to mixing which is faster by a factor of two. The microbaffles introduce a rotational fluid cell in the chamber which continuously deforms and augments the material interface between constituent species. The characteristic time scale for mixing is reduced from O(104 sec.) by mass diffusion alone to O(10 sec.).

This content is only available via PDF.
You do not currently have access to this content.