文献类型：期刊文献

英文题名：Improvement of the bubble separation through eccentric planar cyclones: Experiments and CFD simulations

作者：Xu, Xiao[1];Wang, Shuo[1];Gong, Chunkai[1];Yang, Qiang[1]

机构：[1]East China Univ Sci & Technol, Sch Mech & Power Engn, Shanghai 200237, Peoples R China

年份：2023

卷号：198

起止页码：208

外文期刊名：CHEMICAL ENGINEERING RESEARCH & DESIGN

收录：;EI(收录号：20233914785423);WOS:【SCI-EXPANDED(收录号:WOS:001082060300001)】；

基金：The authors wish to express their sincere gratitude to the National Natural Science Foundation of China (520251032190805722178099) for financial support. This project was also sponsored by "Chenguang Program" supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission (20CG39) .

语种：英文

外文关键词：Planar cyclone; Separation efficiency; Eccentricity; Bubble coalescence; Bubble breakup

摘要：Planar cyclones have great advantages as electrolyzers, photocatalytic reactors, and gas-liquid separators. For planar cyclones, the separation efficiency of bubbles is a key parameter. The effect of eccentricity on bubble separation efficiency in planar cyclones was studied through a combination of experiments and simulations. When eccentricity d, = 0 mm, the separation efficiency of the bubbles decreased with an increase in the liquid injection velocity. This indicates that a greater centrifugal acceleration in planar cyclones does not contribute to bubble separation. Eccentricity d, = -5 mm resulted in a higher bubble separation efficiency. Each planar cyclone was divided into 12 sub-regions with equal areas. When eccentricity d, = -5 mm, subregions 11 and 12 exhibited larger bubble sizes, and a higher bubble separation efficiency was achieved. The area weighted average sauter mean diameter ds reached 0.47 mm and 0.475 mm and area weighted average gas volume fraction s reached 2.75 % in subregion 11 when liquid Reynolds number Rel = 20075.4 and gas Reynolds number Reg = 23.8. The maximum separation efficiency can be increased from 43 % to 60 % when Rel = 20075.4 and Reg = 6.8 when the eccentricity varies from 0 to - 5 mm. Bubble size changes due to coalescence and breakup have an important influence on bubble separation. The trajectory of bubbles exhibits helix. The gradually decreasing curvature radius of the bubble trajectory dominates the bubble separation. Eccentric swirling field provides a sudden decrease in the swirl radius which promotes the reduction of the curvature radius of the bubble trajectory. This study provides an optimization method for the structural design of cyclones.(c) 2023 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.