Drag reduction assisted emulsification in a micro-channel

IF 2.7 2区工程技术 Q2 MECHANICS

Journal of Non-Newtonian Fluid Mechanics Pub Date : 2024-05-14 DOI:10.1016/j.jnnfm.2024.105247

Elia Missi , Agnès Montillet , Jérôme Bellettre , Teodor Burghelea

{"title":"Drag reduction assisted emulsification in a micro-channel","authors":"Elia Missi , Agnès Montillet , Jérôme Bellettre , Teodor Burghelea","doi":"10.1016/j.jnnfm.2024.105247","DOIUrl":null,"url":null,"abstract":"<div><p>An experimental study of the turbulent dynamics of emulsification in a cross-slot microfluidic device is presented. The continuous phase contains a minute amount of an inelastic polymer (xanthan). The Reynolds numbers are sufficiently large (up to 16000) so the drag reduction phenomenon is observed during the emulsification process. The statistics of droplet sizes in the resulting emulsions are measured ex-situ by means of digital microscopy in a wide range of Reynolds numbers and polymer concentrations in the continuous phase. Integral measurements of the statistics of the pressure drops in the micro-channel allow one to systematically map the drag reduction states. Corresponding to each state, the space–time dynamics of the emulsification process are assessed by means of in-situ high speed imaging of the interface between the two fluids which further allows one to extract the characteristic time and space scales associated to the dynamics of the interface. Various dynamic regimes of the microscopic emulsification process are mapped in terms of the Reynolds number and shear thinning rheology of the continuous phase.</p></div>","PeriodicalId":54782,"journal":{"name":"Journal of Non-Newtonian Fluid Mechanics","volume":"329 ","pages":"Article 105247"},"PeriodicalIF":2.7000,"publicationDate":"2024-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Non-Newtonian Fluid Mechanics","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0377025724000636","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"MECHANICS","Score":null,"Total":0}

引用次数: 0

Abstract

An experimental study of the turbulent dynamics of emulsification in a cross-slot microfluidic device is presented. The continuous phase contains a minute amount of an inelastic polymer (xanthan). The Reynolds numbers are sufficiently large (up to 16000) so the drag reduction phenomenon is observed during the emulsification process. The statistics of droplet sizes in the resulting emulsions are measured ex-situ by means of digital microscopy in a wide range of Reynolds numbers and polymer concentrations in the continuous phase. Integral measurements of the statistics of the pressure drops in the micro-channel allow one to systematically map the drag reduction states. Corresponding to each state, the space–time dynamics of the emulsification process are assessed by means of in-situ high speed imaging of the interface between the two fluids which further allows one to extract the characteristic time and space scales associated to the dynamics of the interface. Various dynamic regimes of the microscopic emulsification process are mapped in terms of the Reynolds number and shear thinning rheology of the continuous phase.

Abstract Image

查看原文本刊更多论文

微通道中的减阻辅助乳化技术

本文介绍了对交叉槽微流体装置中乳化湍流动力学的实验研究。连续相中含有微量的非弹性聚合物（黄原胶）。雷诺数足够大（高达 16000），因此在乳化过程中可以观察到阻力减小现象。在雷诺数和连续相中聚合物浓度较宽的范围内，通过数字显微镜对所产生的乳化液中液滴大小的统计数据进行了现场测量。通过对微通道中的压降统计进行综合测量，可以系统地绘制出阻力减小状态图。与每种状态相对应，通过对两种流体之间的界面进行原位高速成像，对乳化过程的时空动态进行评估，从而进一步提取与界面动态相关的特征时间和空间尺度。根据连续相的雷诺数和剪切稀化流变学，绘制了微观乳化过程的各种动态状态。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

Journal of Non-Newtonian Fluid Mechanics 物理-力学

CiteScore

5.00

自引率

19.40%

发文量

109

审稿时长

61 days

期刊介绍： The Journal of Non-Newtonian Fluid Mechanics publishes research on flowing soft matter systems. Submissions in all areas of flowing complex fluids are welcomed, including polymer melts and solutions, suspensions, colloids, surfactant solutions, biological fluids, gels, liquid crystals and granular materials. Flow problems relevant to microfluidics, lab-on-a-chip, nanofluidics, biological flows, geophysical flows, industrial processes and other applications are of interest. Subjects considered suitable for the journal include the following (not necessarily in order of importance): Theoretical, computational and experimental studies of naturally or technologically relevant flow problems where the non-Newtonian nature of the fluid is important in determining the character of the flow. We seek in particular studies that lend mechanistic insight into flow behavior in complex fluids or highlight flow phenomena unique to complex fluids. Examples include Instabilities, unsteady and turbulent or chaotic flow characteristics in non-Newtonian fluids, Multiphase flows involving complex fluids, Problems involving transport phenomena such as heat and mass transfer and mixing, to the extent that the non-Newtonian flow behavior is central to the transport phenomena, Novel flow situations that suggest the need for further theoretical study, Practical situations of flow that are in need of systematic theoretical and experimental research. Such issues and developments commonly arise, for example, in the polymer processing, petroleum, pharmaceutical, biomedical and consumer product industries.