Thermal mixing in T-shaped micromixers with a porous block by the lattice Boltzmann method: Influence of the mixing channel configuration

Abstract

The present paper investigates the thermal mixing and cooling processes in a passive micromixer, which is applicable for the cooling of electronic devices. Employing a porous block and testing different configurations for the mixing channel is considered to enhance the mixing process and cooling performance. A 2D lattice Boltzmann thermal model is utilized to investigate the thermal performance of a T-micromixer with a porous block. Two different types of mixing channel configurations, including a step-shaped and a zigzag-shaped channel, are considered, and the obtained results are compared with those of the simple mixing channel. The thermal mixing and cooling of two miscible fluids, at 50 and 25°C entering the micromixer, are investigated. The results show that changing the mixing channel configuration may create a chaotic laminar flow, which enhances the heat transfer rate between the mixed flow and the channel wall. Whatever the Reynolds number, the step-shaped mixing channel exhibits better mixing performance than the zigzag-shaped one. For the T-micromixer with a zigzag-shaped and step-shaped mixing channel, the cases with h/H = 0.5 and h/H = 0, respectively, exhibit better thermal mixing and cooling performance.

Numerical simulation and parameter optimization of micromixer device using fuzzy logic technique

“…Different types of fields are used in an active micromixer, such as magnetic, 4,5 radio frequency, 6 electroosmotic 7,8 and surface acoustic wave. 9–11 Similarly, a passive micromixer device can have different physiological structures, such as Y-type, 12 T-shape, 13 grooves/obstacles, 14 split–recombine, 15 serpentine 16 and herringbone type structures. 17 The construction of an active micromixer has greater complexity than a passive micromixer.…”