No abstract

No abstract

Due to scale effects, directly enlarging the size of the micromixer is an easy way to reduce the efficiency of mass and heat transfer in the continuous flow chemical process. It is urgently needed to solve the problem of mass and heat transfer efficiency of the scale‐up mixer. A scale‐up microfluidic mixer with a porous structure was designed to improve the mass and heat transfer efficiency using computational fluid dynamics (CFD) simulations. The effects of rotation angle, porosity, and baffle spacing were studied to optimize the mixer structure. Compared with the 1 mm mixer without structure, the scale‐up mixer has a higher mixing efficiency and an 80% reduction in energy consumption at Re ≥ 700. A Nusselt number was used to evaluate the heat transfer efficiency of the mixer during fluid heating. The results show that the porous baffle promotes the generation of secondary flow and enhances the heat transfer effect, making its Nu increase by three times compared with the unstructured mixer. The scale‐up microfluidic mixer with a porous structure can effectively improve the mass and heat transfer performance. This study can provide a reference for the design or development of a novel scale‐up mixer.

The mixing uniformity plays a crucial role in a liquid-liquid two-phase chemical process. To quantify the uniformity of the liquid–liquid process, the specific surface area ratio is proposed and studied through computational fluid dynamics simulation. There is a scale effect in the liquid–liquid two phase chemical processing that the specific surface area ratio decreases to 7.01% when the diameter of the Y-like mixer increases from 1 mm to 10 mm. A millimeter-scale mixer with a fan-notched baffle structure was designed, and the baffle unit length, baffle tilt angle, baffle notch size and baffle thickness of the mixer were optimized. Compared with the 1 mm Y-like mixer, the specific surface area ratio of the 10 mm mixer with notched baffle structures increases to 2.5 times and the treatment capacity increases to 100 times. Additionally, experiment and simulation results prove that FNBS is considered to be a suitable structure for enhancing liquid-liquid two-phase. This study will provide a useful reference for the design of large-scale mixers applicable to liquid-liquid heterogeneous chemical processes.

No abstract