A study on the novel micromixer with chaotic flows

Abstract

This paper presents the novel micro mixer with chaotic flow using coupling between Lorentz force and the moving force of the electric charge in an electric field. Rapid mixing is essential for μ-TAS technology, but is often difficult to achieve it at low Reynolds numbers in micro-systems. Although it is effective to mix with a stirrer for rapid mixing in a general macro-system, it is very difficult to fabricate it in a microsystem. Because the chaotic flow plays a role as a stirrer in a mixing chamber, the novel mixer is expected to mix more rapidly than existing micro mixers. The mixer not only has a simple structure compared with existing ones but also is able to achieve high mixing efficiency in spite of low power consumption. In order to estimate the efficiency for each mixer, the analytical expression and the computer simulations are performed. The results about the flow directions and the experimental results with mixing visualization are presented. Through the comparison with the mixing experiment using the diffusion process, we confirm that the proposed mixer with a simpler structure is able to achieve higher mixing efficiency.