Controlling the Mixing Performance of Passive Micromixers with Variable Section Units.

Changing the structures of microchannels has become an effective strategy for improving the mixing performance of passive micromixers. In this study, we propose a novel micromixer with variable section units through changing the geometric parameters including the type, the position, the number, and the ratio of the variable section units. The effects of these geometric parameters on the mixing performance were numerically investigated and parametrically compared. The results showed that the type of Gra channel, the initial position, a number of 4, and the ratio of 1:4 should be selected. With this selected configuration, the mixing efficiency of the micromixer can be significantly enhanced, with the mixing index exceeding 0.96 at a Reynolds number of 100. These findings demonstrate an effective design strategy for developing passive micromixers.