arXiv: Soft Condensed Matter最新文献_第6页

Interplay of edge fracture and shear banding in complex fluids 复杂流体中边缘断裂与剪切带的相互作用

arXiv: Soft Condensed Matter Pub Date : 2020-05-19 DOI: 10.1122/8.0000086

E. J. Hemingway, S. Fielding

{"title":"Interplay of edge fracture and shear banding in complex fluids","authors":"E. J. Hemingway, S. Fielding","doi":"10.1122/8.0000086","DOIUrl":"https://doi.org/10.1122/8.0000086","url":null,"abstract":"We explore theoretically the interplay between shear banding and edge fracture in complex fluids, by performing a detailed simulation study within two constitutive models: the Johnson-Segalman model and the Giesekus model. We consider separately parameter regimes in which the underlying constitutive curve is monotonic and non-monotonic, such that the bulk flow (in the absence of any edge effects) is respectively homogeneous and shear banded. Phase diagrams of the levels of edge disturbance and of bulk (or quasi-bulk) shear banding are mapped as a function of the surface tension of the fluid-air interface, the wetting angle where this interface meets the walls of the flow cell, and the imposed shear rate. In particular, we explore in more detail the basic result recently announced in Hemingway et al. (2018): that precursors to edge fracture can induce quasi-bulk shear banding. We also appraise analytical predictions that shear banding can induce edge fracture, Skorski and Olmsted (2011). Although a study of remarkable early insight, that study made some strong assumptions about the nature of the \"base state\", which we examine using direct numerical simulation. The basic prediction that shear banding can cause edge fracture remains valid, but with qualitatively modified phase boundaries.","PeriodicalId":8472,"journal":{"name":"arXiv: Soft Condensed Matter","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72712481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 11

Capillary control of collapse in soft composite columns 软质复合柱崩塌的毛细控制

arXiv: Soft Condensed Matter Pub Date : 2020-05-19 DOI: 10.1103/PhysRevMaterials.5.055603

Marc Suñé, J. Wettlaufer

引用次数: 1

Generalized Einstein’s and Brinkman’s solutions for the effective viscosity of nanofluids 纳米流体有效粘度的广义爱因斯坦和布林克曼解

arXiv: Soft Condensed Matter Pub Date : 2020-05-18 DOI: 10.1063/5.0014288

Y. Solyaev, S. Lurie, N. A. Semenov

{"title":"Generalized Einstein’s and Brinkman’s solutions for the effective viscosity of nanofluids","authors":"Y. Solyaev, S. Lurie, N. A. Semenov","doi":"10.1063/5.0014288","DOIUrl":"https://doi.org/10.1063/5.0014288","url":null,"abstract":"In this paper, we derive the closed form analytical solutions for the effective viscosity of the suspensions of solid spheres that take into account the size effects. This result is obtained using the solution for the effective shear modulus of particulate composites developed in the framework of the strain gradient elasticity theory. Assuming incompressibility of matrix and rigid behavior of particles and using a mathematical analogy between the theory of elasticity and the theory of viscous fluids we derive the generalized Einstein's formula for the effective viscosity. Generalized Brinkman's solution for the concentrated suspensions is derived then using differential method. Obtained solutions contain single additional length scale parameter, which can be related to the interactions between base liquid and solid particles in the suspensions. In the case of the large ratio the between diameter of particles and the length scale parameter, developed solutions reduce to the classical solutions, however for the small relative diameter of particles an increase of the effective viscosity is predicted. It is shown that developed models agree well with known experimental data. Solutions for the fibrous suspensions are also derived and validated.","PeriodicalId":8472,"journal":{"name":"arXiv: Soft Condensed Matter","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-05-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88336983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Differences in plasticity between hard and soft spheres 硬球和软球的可塑性差异

arXiv: Soft Condensed Matter Pub Date : 2020-05-15 DOI: 10.1103/PHYSREVRESEARCH.2.023179

P. Morse, Sven Wijtmans, M. V. Deen, M. Hecke, Lisa Manning

引用次数: 14

Dense Pedestrian Crowds Versus Granular Packings: An Analogy of Sorts 密集的步行人群与粒状包装:各种类比

arXiv: Soft Condensed Matter Pub Date : 2020-05-12 DOI: 10.1007/978-3-030-55973-1_51

Alexandre Nicolas

引用次数: 4

Deflection of phototactic microswimmers through obstacle arrays 光致微游泳者通过障碍物阵列的偏转

arXiv: Soft Condensed Matter Pub Date : 2020-05-12 DOI: 10.1103/PHYSREVFLUIDS.5.093302

Marvin Brun-Cosme-Bruny, A. Förtsch, W. Zimmermann, E. Bertin, P. Peyla, S. Rafaï

{"title":"Deflection of phototactic microswimmers through obstacle arrays","authors":"Marvin Brun-Cosme-Bruny, A. Förtsch, W. Zimmermann, E. Bertin, P. Peyla, S. Rafaï","doi":"10.1103/PHYSREVFLUIDS.5.093302","DOIUrl":"https://doi.org/10.1103/PHYSREVFLUIDS.5.093302","url":null,"abstract":"We study the effect of inhomogeneous environments on the swimming direction of the microalgae textit{Chlamydomonas Reinhardtii} (CR) in the presence of a light stimulus. Positive or negative phototaxis describe the ability of microorganisms to bias their swimming towards or away from a light source. Here we consider microswimmers with negative phototaxis in a microfluidic device with a microfabricated square lattice of pillars as obstacles. We measured a mean deflection of microswimmers that shows an interesting nonlinear dependence on the direction of the guiding light beam with respect to the symmetry axes of the pillar lattice. By simulating a model swimmer in a pillar lattice and analyzing its scattering behavior, we identified the width of the reorientation distribution of swimmers to be also crucial for the nonlinear behavior of the swimmer deflection. On the basis of these results we suggest in addition an analytical model for microswimmers, where the pillar lattice is replaced by an anisotropic scattering medium, that depends only on a scattering rate and the width of the reorientation distribution of swimmers. This flexible and handy model fits the experimental results as well. The presented analysis of the deflection of light guided swimmers through pillar lattice may be used for separating swimmers having different reorientation distributions.","PeriodicalId":8472,"journal":{"name":"arXiv: Soft Condensed Matter","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81837301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13

Mechanical approach to surface tension and capillary phenomena 表面张力和毛细现象的机械方法

arXiv: Soft Condensed Matter Pub Date : 2020-05-11 DOI: 10.1119/10.0002411

M. Durand

{"title":"Mechanical approach to surface tension and capillary phenomena","authors":"M. Durand","doi":"10.1119/10.0002411","DOIUrl":"https://doi.org/10.1119/10.0002411","url":null,"abstract":"Many textbooks dealing with surface tension favor the thermodynamic approach (minimization of some thermodynamic potential such as free energy) over the mechanical approach (balance of forces) to describe capillary phenomena, stating that the latter is flawed and misleading. Yet, mechanical approach is more intuitive for students than free energy minimization, and does not require any knowledge of thermodynamics. In this paper we show that capillary phenomena can be unmistakably described using the mechanical approach, as long as the system on which the forces act is properly defined. After reminding the microscopic origin of a tangential tensile force at the interface, we derive the Young-Dupr{e} equation, emphasizing that this relation should be interpreted as an interface condition at the contact line, rather than a force balance equation. This correct interpretation avoids misidentification of capillary forces acting on a given system. Moreover, we show that a reliable method to correctly identify the acting forces is to define a control volume that does not embed any contact line on its surface. Finally, as an illustration of this method, we apply the mechanical approach in a variety of ways on a classic example: the derivation of the equilibrium height of capillary rise (Jurin's law).","PeriodicalId":8472,"journal":{"name":"arXiv: Soft Condensed Matter","volume":"71 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88490242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Impact-induced hardening in dense frictional suspensions 致密摩擦悬浮液的冲击诱发硬化

arXiv: Soft Condensed Matter Pub Date : 2020-05-06 DOI: 10.1103/PHYSREVFLUIDS.6.033301

Pradipto, H. Hayakawa

引用次数: 8

Velocity autocorrelations across the molecular—atomic fluid transformation in hydrogen under pressure 压力下氢分子-原子流体转化的速度自相关性

arXiv: Soft Condensed Matter Pub Date : 2020-05-01 DOI: 10.5488/CMP.23.23607

G. Ruocco, T. Bryk, C. Pierleoni, A. Seitsonen

引用次数: 2

Towards the description of water adsorption in slit-like nanochannels with grafted molecular brushes. Density functional theory 接枝分子刷在裂隙状纳米通道中吸附水的研究。密度泛函理论

arXiv: Soft Condensed Matter Pub Date : 2020-05-01 DOI: 10.5488/CMP.23.23604

V. M. Trejos, M. Aguilar, S. Sokołowski, O. Pizio

引用次数: 0