CFD Analysis of Flow Patterns and Micromixing Efficiency in a Y-Type Microchannel Reactor

Abstract

Micromixing efficiency is a significant performance index of most chemical reactors. In this work, a three-dimensional Computational Fluid Dynamics (CFD) model for a Y-type microchannel reactor has been developed to predict its flow patterns and micromixing efficiency with the iodate–iodide reaction testing system. The effects of Re, volumetric flow ratio (R), and initial concentration of H+ on the micromixing efficiency (represented by the segregation index XS) have been investigated and the visualization of velocity, path lines, and concentration distributions inside the reactor has been demonstrated. It was found that XS decreases with increasing Re, or decreasing R or initial H+ concentration. To optimize the microchannel reactor for enhanced mixing performance, the effects of microchannel configuration, such as length of channel, mixing angle, and hydraulic diameters, on micromixing efficiency were studied as well. The results demonstrated that the mixing process mainly occurs in the Y-junction area and extra length of outlet channel has little effect on micromixing efficiency. It also showed that XS depends strongly on the mixing angle and hydraulic diameters of the channels, and the pressure drop within the channel increases significantly with decreasing hydraulic diameters.