{"title":"Analysis of the number of topological defects in active nematic fluids under applied shear flow","authors":"Zhenna Li, Hao Ye, Jianzhong Lin, Zhenyu Ouyang","doi":"10.1140/epje/s10189-024-00437-4","DOIUrl":null,"url":null,"abstract":"<div><p>The number of topological defects in the shear flow of active nematic fluids is numerically investigated in this study. The evolution of the flow state of extensile active nematic fluids is explored by increasing the activity of active nematic fluids. Evidently, medium-activity active nematic fluids exhibit a highly ordered vortex lattice fluid state. However, high-activity active nematic fluids exhibit a meso-scale turbulent flow accompanied by topological defects. The number of topological defects (<i>N</i><sub>def</sub>) increases with increasing shear Reynolds number (<i>R</i>e<sub>s</sub>). Fluid viscosity strongly influences <i>N</i><sub>def</sub>, while the influence of fluid density is relatively weak. <i>N</i><sub>def</sub> decreases with increasing activity length scale (<i>l</i><sub><i>ζ</i></sub>) value. A small <i>Re</i><sub>s</sub> value strongly influences <i>N</i><sub>def</sub>, whereas a large <i>l</i><sub><i>ζ</i></sub> value only weakly influences <i>N</i><sub>def</sub>. As the activity increases, <i>N</i><sub>def</sub> in contractile active nematic fluids becomes larger than that of extensile active nematic fluids.</p><h3>Graphical abstract</h3>\n<div><figure><div><div><picture><source><img></source></picture></div><div><p>Graphical abstract represents the flow state of meso-scale turbulent accompanied by topological defects. For the two dimensional case, two types of topological defects, namely comet-like + 1/2 and trefoil-like − 1/2 topological defects</p></div></div></figure></div></div>","PeriodicalId":790,"journal":{"name":"The European Physical Journal E","volume":"47 6","pages":""},"PeriodicalIF":1.8000,"publicationDate":"2024-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"The European Physical Journal E","FirstCategoryId":"4","ListUrlMain":"https://link.springer.com/article/10.1140/epje/s10189-024-00437-4","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
The number of topological defects in the shear flow of active nematic fluids is numerically investigated in this study. The evolution of the flow state of extensile active nematic fluids is explored by increasing the activity of active nematic fluids. Evidently, medium-activity active nematic fluids exhibit a highly ordered vortex lattice fluid state. However, high-activity active nematic fluids exhibit a meso-scale turbulent flow accompanied by topological defects. The number of topological defects (Ndef) increases with increasing shear Reynolds number (Res). Fluid viscosity strongly influences Ndef, while the influence of fluid density is relatively weak. Ndef decreases with increasing activity length scale (lζ) value. A small Res value strongly influences Ndef, whereas a large lζ value only weakly influences Ndef. As the activity increases, Ndef in contractile active nematic fluids becomes larger than that of extensile active nematic fluids.
期刊介绍:
EPJ E publishes papers describing advances in the understanding of physical aspects of Soft, Liquid and Living Systems.
Soft matter is a generic term for a large group of condensed, often heterogeneous systems -- often also called complex fluids -- that display a large response to weak external perturbations and that possess properties governed by slow internal dynamics.
Flowing matter refers to all systems that can actually flow, from simple to multiphase liquids, from foams to granular matter.
Living matter concerns the new physics that emerges from novel insights into the properties and behaviours of living systems. Furthermore, it aims at developing new concepts and quantitative approaches for the study of biological phenomena. Approaches from soft matter physics and statistical physics play a key role in this research.
The journal includes reports of experimental, computational and theoretical studies and appeals to the broad interdisciplinary communities including physics, chemistry, biology, mathematics and materials science.