Mixing of fluids in a micromixer with staggered T-shaped cross-sections

• Main Authors: Shu-WeiHuang, 黃書瑋
• Other Authors: Chih-Yang Wu
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/79404854085217016275

碩士 === 國立成功大學 === 機械工程學系 === 102 === We propose a micromixer which allows two different fluids to flow into the main channel consisting of modular subsections with staggered T-shaped cross-sections. The simulation results obtained by the software, CFDRC, show the following trend. When mixing fluid flows into a T-shaped cross-section subsection with center moved to the right (represented by symbol A) and a following T-shaped cross-section subsection with center moved to the left (represented by symbol B), a longitudinal vortex is induced. The vortex persists in the following square cross-section subsection (represented by symbol C) and enhances mixing for the case with a small Reynolds number (≤ 10). Next, we fabricate the micromixer by photolithography and apply a confocal microscopy to acquire the mixing flow images. The comparisons of the simulation results and the images show qualitative agreement. Finally, we adopt the Taguchi method to select better parameters, including the length of the first and the second T-shaped cross-section subsection (la and lb), that of the square cross-section subsection (lc) and the arrangement of modules. The simulation based on the Taguchi method shows that the effectiveness of the parameters is ranked as: the arrangement of modules 〉 lb 〉 lc 〉 la and the mixing efficiency of the micromixer with la = 0.75Wm, lb = Wm, lc = 0.75Wm (with Wm denoting the main channel width) and the staggered cross-sections of each of the twelve modules arranged in the order of A, B and C is higher than that of the other similar micromixers.