Numerical study of the performance of an active micromixer based on the oscillations of a microbeam.

[Display omitted] • A 3D numerical study was conducted on a micromixer with an oscillating microbeam. • Effects of oscillation frequency and Reynolds number on mixing were investigated. • The optimum operating condition was found for this micromixer. • Four novel designs were proposed by adding passive techniques to this micromixer. • The maximum mixing index was 88% in 0.4 s. In this research, we numerically studied a three-dimensional (3-D) T-shaped active micromixer which works based on the oscillations of a cantilever microbeam. We explored the influence of microbeam's oscillation frequency (10–40 Hz) and flow Reynolds number (2.5–30) on mixing performance, revealing optimal operating conditions. Under optimal operating conditions, using a simple microbeam in a short straight microchannel, the micromixer achieved a 76.7 % mixing index within just 0.4 s. In the next part of this paper, we introduced modifications to the microbeam and microchannel geometries to enhance mixing performance further. Adding a circular part to the channel improved the mixing index to 85.7 %. In a more complex configuration, characterized by a perforated microbeam and a circular microchannel, the micromixer achieved its highest efficiency of 88 %. Additionally, a novel configuration employing two microbeams within a straight channel achieved a mixing efficiency of 82.2 %. [ABSTRACT FROM AUTHOR]