Mixing performance of T-shaped wavy-walled micromixers with embedded obstacles

This research systematically investigates the impact of microchannel geometry on key parameters governing mixing efficiency and cost. The study focuses on passive T-shaped micromixers with modified sinusoidal wavy walls, analyzing a spectrum of configurations ranging from the raccoon to serpentine by varying the wall phase angles. The traditional T-shaped micromixer serves as a foundational reference, and we systematically vary phase angles, amplitudes, and wavelengths of the wavy walls to comprehensively address all possible configurations. Additionally, different shaped obstacles such as circular, square, diamond, and triangular obstacles are strategically introduced to further enhance mixing performance. The findings reveal intricate relationships and dependencies among geometric factors, shedding light on configurations that significantly enhance mixing efficiencies. Notably, a specific wavy micromixer configuration, characterized by a carefully tuned phase difference, amplitude, and wavelength, exhibits the highest mixing index in the absence of obstacles. The introduction of obstacles, particularly circular ones, further enhances mixing efficiency. As Reynolds (Re) and Schmidt (Sc) numbers increase, the mixing index decreases, and the mixing cost rises. This work adds a quantitative dimension to understanding the interplay between geometric parameters, flow conditions, and mixing performance in passive micromixers with systematic wavy walls and embedded obstacles.