Mixing performance of a novel passive micromixer
with logarithmic spiral channel
He Xiuhua1, Wei Dandan1, Deng Zhidan2, Yang Song3, Cai Shengchuan1
1.School of Energy and Power Engineering, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 2.Faculty of Science, Jiangsu University, Zhenjiang, Jiangsu 212013, China; 3.National Research Center of Pumps, Jiangsu University, Zhenjiang, Jiangsu 212013, China
Abstract：A passive micromixer with logarithmic spiral channel is presented in this paper. The channel is composed of two logarithmic spiral casings, and the spiral polar angle varies from 0° to 180°. The mixing performance of the micromixer is analyzed by simulating the laminar flow in it at Reynolds numbers between 0.2 and 100.0. The results show that the mixing index at the exit of the mixer decreases with increasing Reynolds number until the number arrives at 5.0. However, once Reynolds number is larger than 5.0, the mixing index at the exit increases with increasing Reynolds number. At a Reynolds number of 0.2, the influence of both coefficient b2 and width w on the mixing performance is quite little, and the mixing index is ranged from 0.6 to 0.8. The influences of the two factors on the mixing index increase with the increase of Reynolds number. At a Reynolds number of above 50.0, and b2 =0.35-0.50 as well as w=0.05-0.13, the mixing index is greater, suggesting the micromixer has exhibited a better performance.
