1
|
Voulgarakis NK. Multilayered noise model for transport in complex environments. Phys Rev E 2023; 108:064105. [PMID: 38243501 DOI: 10.1103/physreve.108.064105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 11/09/2023] [Indexed: 01/21/2024]
Abstract
Transport in complex fluidic environments often exhibits transient subdiffusive dynamics accompanied by non-Gaussian probability density profiles featuring a nonmonotonic non-Gaussian parameter. Such properties cannot be adequately explained by the original theory of Brownian motion. Based on an extension of kinetic theory, this study introduces a chain of hierarchically coupled random walks approach that effectively captures all these intriguing characteristics. If the environment consists of a series of independent white noise sources, then the problem can be expressed as a system of hierarchically coupled Ornstein-Uhlenbech equations. Due to the linearity of the system, the most essential transport properties have a closed analytical form.
Collapse
Affiliation(s)
- Nikolaos K Voulgarakis
- Department of Mathematics and Statistics, Washington State University, Pullman, Washington 99164, USA
| |
Collapse
|
2
|
Morgan ML, James DW, Monloubou M, Olsen KS, Sandnes B. Subdiffusion model for granular discharge in a submerged silo. Phys Rev E 2021; 104:044908. [PMID: 34781574 DOI: 10.1103/physreve.104.044908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 10/04/2021] [Indexed: 11/07/2022]
Abstract
Silo discharge has been extensively studied for decades although questions remain regarding the nature of the velocity field, particularly for submerged systems. In this work, fluid-driven granular drainage was performed in a quasi-two-dimensional silo with grains submerged in fluid. While the observed Gaussian velocity profiles were generally consistent with current diffusion models, the diffusion length was found to significantly decrease with height in contrast to the increases previously seen in dry silos. We propose a phenomenological anomalous diffusion model for the spreading of the flow upwards in the cell, with the fluid-driven flows we study here falling in the category of subdiffusive behavior. As the viscous characteristics of the system were amplified, the diffusion length increased and the shape of the flowing zone in the silo changed, deviating further from the parabolic form predicted by traditional normal diffusion models, in effect becoming more subdiffusive as quantified by a decreasing diffusion exponent.
Collapse
Affiliation(s)
- Miles L Morgan
- Faculty of Science and Engineering, Swansea University, Bay Campus, Swansea SA1 8EN, United Kingdom
| | - David W James
- Faculty of Science and Engineering, Swansea University, Bay Campus, Swansea SA1 8EN, United Kingdom
| | - Martin Monloubou
- Faculty of Science and Engineering, Swansea University, Bay Campus, Swansea SA1 8EN, United Kingdom
| | - Kristian S Olsen
- PoreLab, Department of Physics, University of Oslo, Blindern, 0316 Oslo, Norway
| | - Bjørnar Sandnes
- Faculty of Science and Engineering, Swansea University, Bay Campus, Swansea SA1 8EN, United Kingdom
| |
Collapse
|
3
|
Wang D, Dijksman JA, Barés J, Zheng H. Strain dependent vorticity in sheared granular media. EPJ WEB OF CONFERENCES 2021. [DOI: 10.1051/epjconf/202124902010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Displacement fields in sheared particle packings often display vortex-like structures that reveal essential features about the mechanical state of the collection of particles. There are several metrics to quantify these flow field features, yet extracting such quantitative metrics from flow field or particle tracking data involves making numerous choices on the time and length scales over which to average. Here we employ a much used experimental data set on sheared disk packings to explore how such arbitrary data mining choices affect the obtained results. We focus on calculating the strain dependent vorticity, as this metric is a differential method hence potentially sensitive to the way it is computed. We find that the total surface area with an absolute vorticity above a certain threshold approaches a plateau value as shear progresses. This plateau value exhibits a non-monotonic dependence on packing fraction. We also show which range of choices yields results that can support an analysis method independent, physical interpretation of the flow field data.
Collapse
|
4
|
Rognon P, Macaulay M. Shear-induced diffusion in dense granular fluids. SOFT MATTER 2021; 17:5271-5277. [PMID: 34008690 DOI: 10.1039/d1sm00422k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Granular materials are comprised of solid, athermal grains. Whilst immune to thermal motion, these grains move and diffuse when they undergo shear deformation. Here we introduce this process of shear-induced diffusion with a focus on dense flows. The goal is to present the established scaling laws for continuum diffusivity and to relate them to the micro-mechanisms of a granular random walk. We then suggest how this knowledge may help advance our understanding of granular rheology and diffusion in other soft-materials.
Collapse
Affiliation(s)
- Pierre Rognon
- Particles and Grains Laboratory, School of Civil Engineering, The University of Sydney, Sydney, NSW 2006, Australia.
| | - Matthew Macaulay
- Particles and Grains Laboratory, School of Civil Engineering, The University of Sydney, Sydney, NSW 2006, Australia.
| |
Collapse
|
5
|
Sarkar T, Chaudhuri P, Sain A. Poiseuille Flow of Soft Polycrystals in 2D Rough Channels. PHYSICAL REVIEW LETTERS 2020; 124:158003. [PMID: 32357064 DOI: 10.1103/physrevlett.124.158003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 07/10/2019] [Accepted: 03/16/2020] [Indexed: 06/11/2023]
Abstract
Polycrystals are partially ordered solids where crystalline order extends over mesoscopic length scales, namely, the grain size. We study the Poisuielle flow of such materials in a rough channel. In general, similar to yield stress fluids, three distinct dynamical states, namely, flowing, stick-slip, and jammed can be observed, with a yield threshold dependent on channel width. Importantly, the interplay between the finite channel width, and the intrinsic ordering scale (the grain size) leads to a new type of spatiotemporal heterogeneity. In wide channels, although the average flow profile remains pluglike, at the underlying granular level, there is vigorous grain remodeling activity resulting from the velocity heterogeneity among the grains. As the channel width approaches typical grain size, the flowing polycrystalline state breaks up into a spatially heterogeneous mixture of flowing liquid like patches and chunks of nearly static grains. Despite these static grains, the average velocity still shows a parabolic profile, dominated by the moving liquidlike patches. However, the solid-liquid front moves at nearly constant speed in the opposite direction of the external drive.
Collapse
Affiliation(s)
- Tanmoy Sarkar
- Department of Physics, Indian Institute of Technology, Bombay, Powai, Mumbai 400 076, India
| | - Pinaki Chaudhuri
- Institute of Mathematical Sciences, CIT Campus, Taramani, Chennai 600113, India
| | - Anirban Sain
- Department of Physics, Indian Institute of Technology, Bombay, Powai, Mumbai 400 076, India
| |
Collapse
|
6
|
Qi F, de Richter SK, Jenny M, Peters B. DEM simulation of dense granular flows in a vane shear cell: Kinematics and rheological laws. POWDER TECHNOL 2020. [DOI: 10.1016/j.powtec.2020.03.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
7
|
Chen Y, Wang W. Reticulate collisional structure in boundary-driven granular gases. Phys Rev E 2019; 100:042908. [PMID: 31770908 DOI: 10.1103/physreve.100.042908] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Indexed: 11/07/2022]
Abstract
We report a peculiar head-on collision network between two vibrating boundaries in experiments performed during a parabolic flight and in a laboratory using horizontal vibration. This structure is a new ordering, which is due to an orientation correlation between the relative position and velocity of any particle pair. It weakens the collision frequency and produces a long-range boundary effect. Moreover, we find the molecular chaos assumption is violated in a larger portion of the phase space. Using an anisotropic distribution model, we modify angular integration results and compare them to the results of the kinetic theory.
Collapse
Affiliation(s)
- Yanpei Chen
- State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Wei Wang
- State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China and University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| |
Collapse
|
8
|
Witzel P, Götz M, Lanoiselée Y, Franosch T, Grebenkov DS, Heinrich D. Heterogeneities Shape Passive Intracellular Transport. Biophys J 2019; 117:203-213. [PMID: 31278001 PMCID: PMC6700759 DOI: 10.1016/j.bpj.2019.06.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 05/22/2019] [Accepted: 06/11/2019] [Indexed: 01/06/2023] Open
Abstract
A living cell's interior is one of the most complex and intrinsically dynamic systems, providing an elaborate interplay between cytosolic crowding and ATP-driven motion that controls cellular functionality. Here, we investigated two distinct fundamental features of the merely passive, non-biomotor-shuttled material transport within the cytoplasm of Dictyostelium discoideum cells: the anomalous non-linear scaling of the mean-squared displacement of a 150-nm-diameter particle and non-Gaussian distribution of increments. Relying on single-particle tracking data of 320,000 data points, we performed a systematic analysis of four possible origins for non-Gaussian transport: 1) sample-based variability, 2) rarely occurring strong motion events, 3) ergodicity breaking/aging, and 4) spatiotemporal heterogeneities of the intracellular medium. After excluding the first three reasons, we investigated the remaining hypothesis of a heterogeneous cytoplasm as cause for non-Gaussian transport. A, to our knowledge, novel fit model with randomly distributed diffusivities implementing medium heterogeneities suits the experimental data. Strikingly, the non-Gaussian feature is independent of the cytoskeleton condition and lag time. This reveals that efficiency and consistency of passive intracellular transport and the related anomalous scaling of the mean-squared displacement are regulated by cytoskeleton components, whereas cytoplasmic heterogeneities are responsible for the generic, non-Gaussian distribution of increments.
Collapse
Affiliation(s)
- Patrick Witzel
- Faculty for Chemistry and Pharmacy, Julius-Maximilians-Universität Würzburg, Würzburg, Germany; Fraunhofer Institute for Silicate Research ISC, Würzburg, Germany
| | - Maria Götz
- Faculty for Chemistry and Pharmacy, Julius-Maximilians-Universität Würzburg, Würzburg, Germany; Fraunhofer Institute for Silicate Research ISC, Würzburg, Germany
| | - Yann Lanoiselée
- Laboratoire de Physique de la Matière Condensée, CNRS-Ecole Polytechnique, Palaiseau, France
| | - Thomas Franosch
- Institut für Theoretische Physik, Universität Innsbruck, Innsbruck, Austria
| | - Denis S Grebenkov
- Laboratoire de Physique de la Matière Condensée, CNRS-Ecole Polytechnique, Palaiseau, France
| | - Doris Heinrich
- Fraunhofer Institute for Silicate Research ISC, Würzburg, Germany; Leiden Institute of Physics, Huygens-Kamerlingh Onnes Laboratory, Leiden University, Leiden, the Netherlands.
| |
Collapse
|
9
|
Salili SM, Harrington M, Durian DJ. Note: Eliminating stripe artifacts in light-sheet fluorescence imaging. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:036107. [PMID: 29604752 DOI: 10.1063/1.5016546] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
We report two techniques to mitigate stripe artifacts in light-sheet fluorescence imaging. The first uses an image processing algorithm called the multidirectional stripe remover method to filter stripes from an existing image. The second uses an elliptical holographic diffuser with strong scattering anisotropy to prevent stripe formation during image acquisition. These techniques facilitate accurate interpretation of image data, especially in denser samples. They are also facile and cost-effective.
Collapse
Affiliation(s)
- S M Salili
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - M Harrington
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - D J Durian
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| |
Collapse
|
10
|
Endo K, Katsuragi H. Statistical properties of gravity-driven granular discharge flow under the influence of an obstacle. EPJ WEB OF CONFERENCES 2017. [DOI: 10.1051/epjconf/201714003004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
11
|
Weis S, Schröter M. Analyzing X-ray tomographies of granular packings. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:051809. [PMID: 28571396 DOI: 10.1063/1.4983051] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Starting from three-dimensional volume data of a granular packing, as, e.g., obtained by X-ray Computed Tomography, we discuss methods to first detect the individual particles in the sample and then analyze their properties. This analysis includes the pair correlation function, the volume and shape of the Voronoi cells, and the number and type of contacts formed between individual particles. We mainly focus on packings of monodisperse spheres, but we will also comment on other monoschematic particles such as ellipsoids and tetrahedra. This paper is accompanied by a package of free software containing all programs (including source code) and an example three-dimensional dataset which allows the reader to reproduce and modify all examples given.
Collapse
Affiliation(s)
- Simon Weis
- Institut für Theoretische Physik I, Friedrich-Alexander-Universität, 91058 Erlangen, Germany
| | - Matthias Schröter
- Institute for Multiscale Simulation, Friedrich-Alexander-Universität, 91052 Erlangen, Germany
| |
Collapse
|
12
|
Amon A, Born P, Daniels KE, Dijksman JA, Huang K, Parker D, Schröter M, Stannarius R, Wierschem A. Preface: Focus on imaging methods in granular physics. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:051701. [PMID: 28571403 DOI: 10.1063/1.4983052] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Affiliation(s)
- Axelle Amon
- Institut de Physique de Rennes, UMR UR1-CNRS 6251, Université de Rennes 1, 35042 Rennes, France
| | - Philip Born
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt, 51170 Cologne, Germany
| | - Karen E Daniels
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - Joshua A Dijksman
- Physical Chemistry and Soft Matter, Wageningen University and Research, Wageningen, The Netherlands
| | - Kai Huang
- Experimentalphysik V, Universität Bayreuth, 95440 Bayreuth, Germany
| | - David Parker
- School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - Matthias Schröter
- Institute for Multiscale Simulation, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91052 Erlangen, Germany
| | - Ralf Stannarius
- Institut für Experimentelle Physik, Otto-von-Guericke-Universität, 39106 Magdeburg, Germany
| | - Andreas Wierschem
- Institute of Fluid Mechanics, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| |
Collapse
|
13
|
Sano TG, Kanazawa K, Hayakawa H. Granular rotor as a probe for a nonequilibrium bath. Phys Rev E 2016; 94:032910. [PMID: 27739823 DOI: 10.1103/physreve.94.032910] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Indexed: 11/07/2022]
Abstract
This study numerically and analytically investigates the dynamics of a rotor under viscous or dry friction as a nonequilibrium probe of a granular gas. In order to demonstrate the role of the rotor as a probe for a nonequilibrium bath, the molecular dynamics (MD) simulation of the rotor is performed under viscous or dry friction surrounded by a steady granular gas under gravity. A one-to-one map between the velocity distribution function (VDF) of the granular gas and the angular distribution function for the rotor is theoretically derived. The MD simulation demonstrates that the one-to-one map accurately infers the local VDF of the granular gas from the angular VDF of the rotor, and vice versa.
Collapse
Affiliation(s)
- Tomohiko G Sano
- Yukawa Institute for Theoretical Physics, Kyoto University, Kitashirakawa-oiwake cho, Sakyo-ku, Kyoto 606-8502, Japan
| | - Kiyoshi Kanazawa
- Department of Computational Intelligence and Systems Science, Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, 4259-G3-52 Nagatsuta-cho, Midori-ku, Yokohama 226-8503, Japan
| | - Hisao Hayakawa
- Yukawa Institute for Theoretical Physics, Kyoto University, Kitashirakawa-oiwake cho, Sakyo-ku, Kyoto 606-8502, Japan
| |
Collapse
|
14
|
Wilson TJ, Pfeifer CR, Mesyngier N, Durian DJ. Granular discharge rate for submerged hoppers. PAPERS IN PHYSICS 2014. [DOI: 10.4279/pip.060009] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
|
15
|
Gnoli A, Puglisi A, Sarracino A, Vulpiani A. Nonequilibrium Brownian motion beyond the effective temperature. PLoS One 2014; 9:e93720. [PMID: 24714671 PMCID: PMC3979703 DOI: 10.1371/journal.pone.0093720] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 03/05/2014] [Indexed: 11/19/2022] Open
Abstract
The condition of thermal equilibrium simplifies the theoretical treatment of fluctuations as found in the celebrated Einstein’s relation between mobility and diffusivity for Brownian motion. Several recent theories relax the hypothesis of thermal equilibrium resulting in at least two main scenarios. With well separated timescales, as in aging glassy systems, equilibrium Fluctuation-Dissipation Theorem applies at each scale with its own “effective” temperature. With mixed timescales, as for example in active or granular fluids or in turbulence, temperature is no more well-defined, the dynamical nature of fluctuations fully emerges and a Generalized Fluctuation-Dissipation Theorem (GFDT) applies. Here, we study experimentally the mixed timescale regime by studying fluctuations and linear response in the Brownian motion of a rotating intruder immersed in a vibro-fluidized granular medium. Increasing the packing fraction, the system is moved from a dilute single-timescale regime toward a denser multiple-timescale stage. Einstein’s relation holds in the former and is violated in the latter. The violation cannot be explained in terms of effective temperatures, while the GFDT is able to impute it to the emergence of a strong coupling between the intruder and the surrounding fluid. Direct experimental measurements confirm the development of spatial correlations in the system when the density is increased.
Collapse
Affiliation(s)
- Andrea Gnoli
- Istituto dei Sistemi Complessi - Consiglio Nazionale delle Ricerche, Rome, Italy
- Dipartimento di Fisica, Università “Sapienza”, Rome, Italy
| | - Andrea Puglisi
- Istituto dei Sistemi Complessi - Consiglio Nazionale delle Ricerche, Rome, Italy
- Dipartimento di Fisica, Università “Sapienza”, Rome, Italy
- * E-mail:
| | - Alessandro Sarracino
- Istituto dei Sistemi Complessi - Consiglio Nazionale delle Ricerche, Rome, Italy
- Dipartimento di Fisica, Università “Sapienza”, Rome, Italy
- Laboratoire de Physique Théorique de la Matière Condensée - Centre National de la Recherche Scientifique Unité mixte de recherche 7600, Université Paris 6, Paris, France
| | - Angelo Vulpiani
- Istituto dei Sistemi Complessi - Consiglio Nazionale delle Ricerche, Rome, Italy
- Dipartimento di Fisica, Università “Sapienza”, Rome, Italy
| |
Collapse
|
16
|
Ellowitz J, Turlier H, Guttenberg N, Zhang WW, Nagel SR. Still water: dead zones and collimated ejecta from the impact of granular jets. PHYSICAL REVIEW LETTERS 2013; 111:168001. [PMID: 24182302 DOI: 10.1103/physrevlett.111.168001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Indexed: 06/02/2023]
Abstract
When a dense granular jet hits a target, it forms a large dead zone and ejects a highly collimated conical sheet with a well-defined opening angle. Using experiments, simulations, and continuum modeling, we find that this opening angle is insensitive to the precise target shape and the dissipation mechanisms in the flow. We show that this surprising insensitivity arises because dense granular jet impact, though highly dissipative, is nonetheless controlled by the limit of perfect fluid flow.
Collapse
Affiliation(s)
- Jake Ellowitz
- Department of Physics and the James Franck Institute, University of Chicago, Chicago, Illinois 60637, USA
| | | | | | | | | |
Collapse
|
17
|
Miller T, Rognon P, Metzger B, Einav I. Eddy viscosity in dense granular flows. PHYSICAL REVIEW LETTERS 2013; 111:058002. [PMID: 23952446 DOI: 10.1103/physrevlett.111.058002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Indexed: 06/02/2023]
Abstract
We present a seminal set of experiments on dense granular flows in the stadium shear geometry. The advantage of this geometry is that it produces steady shear flow over large deformations, in which the shear stress is constant. The striking result is that the velocity profiles exhibit an S shape, and are not linear as local constitutive laws would predict. We propose a model that suggests this is a result of wall perturbations which span through the system due to the nonlocal behavior of the material. The model is analogous to that of eddy viscosity in turbulent boundary layers, in which the distance to the wall is introduced to predict velocity profiles. Our findings appear pivotal in a number of experimental and practical situations involving dense granular flows next to a boundary. They could further be adapted to other similar materials such as dense suspensions, foams, or emulsions.
Collapse
Affiliation(s)
- T Miller
- Particles and Grains Laboratory, School of Civil Engineering, The University of Sydney, Sydney, New South Wales 2006, Australia
| | | | | | | |
Collapse
|
18
|
Wang B, Kuo J, Bae SC, Granick S. When Brownian diffusion is not Gaussian. NATURE MATERIALS 2012; 11:481-5. [PMID: 22614505 DOI: 10.1038/nmat3308] [Citation(s) in RCA: 273] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Affiliation(s)
- Bo Wang
- Department of Materials Science and Engineering, University of Illinois, Urbana, Illinois 61801, USA
| | | | | | | |
Collapse
|
19
|
Dijksman JA, Rietz F, Lorincz KA, van Hecke M, Losert W. Invited Article: Refractive index matched scanning of dense granular materials. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2012; 83:011301. [PMID: 22299922 DOI: 10.1063/1.3674173] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We review an experimental method that allows to probe the time-dependent structure of fully three-dimensional densely packed granular materials and suspensions by means of particle recognition. The method relies on submersing a granular medium in a refractive index matched fluid. This makes the resulting suspension transparent. The granular medium is then visualized by exciting, layer by layer, the fluorescent dye in the fluid phase. We collect references and unreported experimental know-how to provide a solid background for future development of the technique, both for new and experienced users.
Collapse
Affiliation(s)
- Joshua A Dijksman
- Physics Department, Duke University, Durham, North Carolina 27708-0305, USA
| | | | | | | | | |
Collapse
|
20
|
Garcimartín A, Zuriguel I, Janda A, Maza D. Fluctuations of grains inside a discharging two-dimensional silo. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 84:031309. [PMID: 22060363 DOI: 10.1103/physreve.84.031309] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 08/24/2011] [Indexed: 05/31/2023]
Abstract
We present experimental data corresponding to a two-dimensional dense granular flow, namely, the gravity-driven discharge of grains from a small opening in a silo. We study the local velocity field at the scale of single grains at different places with the help of particle-tracking techniques. From these data, the velocity profiles can be obtained and the validity of some long-standing approaches can be assessed. Moreover, the fluctuations of the velocities are taken into consideration to characterize the features of the advective motion (due to the gravity force) and the diffusive motion, which shows nontrivial behavior.
Collapse
Affiliation(s)
- Angel Garcimartín
- Departamento de Física, Facultad de Ciencias, Universidad de Navarra, E-31080 Pamplona, Spain.
| | | | | | | |
Collapse
|
21
|
Mukhopadhyay S, Peixinho J. Packings of deformable spheres. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 84:011302. [PMID: 21867159 DOI: 10.1103/physreve.84.011302] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Revised: 06/17/2011] [Indexed: 05/31/2023]
Abstract
We present an experimental study of disordered packings of deformable spheres. Fluorescent hydrogel spheres immersed in water together with a tomography technique enabled the imaging of the three-dimensional arrangement. The mechanical behavior of single spheres subjected to compression is first examined. Then the properties of packings of a randomized collection of deformable spheres in a box with a moving lid are tested. The transition to a state where the packing withstands finite stresses before yielding is observed. Starting from random packed states, the power law dependence of the normal force versus packing fraction or strain at different velocities is quantified. Furthermore, a compression-decompression sequence at low velocities resulted in rearrangements of the spheres. At larger packing fractions, a saturation of the mean coordination number took place, indicating the deformation and faceting of the spheres.
Collapse
|
22
|
Panaitescu A, Kudrolli A. Spatial distribution functions of random packed granular spheres obtained by direct particle imaging. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2010; 81:060301. [PMID: 20866367 DOI: 10.1103/physreve.81.060301] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Indexed: 05/29/2023]
Abstract
We measure the two-point density correlations and Voronoi cell distributions of cyclically sheared granular spheres obtained with a fluorescence technique and compare them with random packing of frictionless spheres. We find that the radial distribution function g(r) is captured by the Percus-Yevick equation for initial volume fraction ϕ=0.59. However, small but systematic deviations are observed because of the splitting of the second peak as ϕ is increased toward random close packing. The distribution of the Voronoi free volumes deviates from postulated Γ distributions, and the orientational order metric Q6 shows local order but no long range order. Overall, these measures show significant similarity of random packing of granular and frictionless spheres, but some systematic differences as well.
Collapse
Affiliation(s)
- Andreea Panaitescu
- Department of Physics, Clark University, Worcester, Massachusetts 01610, USA
| | | |
Collapse
|
23
|
Rycroft CH, Orpe AV, Kudrolli A. Physical test of a particle simulation model in a sheared granular system. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 80:031305. [PMID: 19905108 DOI: 10.1103/physreve.80.031305] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Revised: 06/16/2009] [Indexed: 05/28/2023]
Abstract
We report a detailed comparison of a slow gravity-driven sheared granular flow with a discrete-element simulation performed in the same geometry. In the experiments, grains flow inside a silo with a rectangular cross section and are sheared by a rough boundary on one side and smooth boundaries on the other sides. Individual grain position and motion are measured using a particle index-matching imaging technique where a fluorescent dye is added to the interstitial liquid which has the same refractive index as the glass beads. The simulations use a Cundall-Strack contact model between the grains using contact parameters that have been used in many other previous studies and ignore the hydrodynamic effects of the interstitial liquid. Computations are performed to understand the effect of particle coefficient of friction, elasticity, contact model, and polydispersity on mean flow properties. We then perform a detailed comparison of the particle fluctuation properties as measured by the displacement probability distribution function and the mean square displacement. All in all, our study suggests a high level of quantitative agreement between the simulations and experiments.
Collapse
Affiliation(s)
- Chris H Rycroft
- Department of Mathematics, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
| | | | | |
Collapse
|
24
|
Fiege A, Aspelmeier T, Zippelius A. Long-time tails and cage effect in driven granular fluids. PHYSICAL REVIEW LETTERS 2009; 102:098001. [PMID: 19392566 DOI: 10.1103/physrevlett.102.098001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2008] [Indexed: 05/27/2023]
Abstract
We study the velocity autocorrelation function of a driven granular fluid in the stationary state in three dimensions. As the critical volume fraction of the glass transition in the corresponding elastic system is approached, we observe pronounced cage effects in the velocity autocorrelation function as well as a strong decrease of the diffusion constant, depending on the inelasticity. At moderate densities the velocity autocorrelation function is shown to decay algebraically in time, like t(-3/2), if momentum is conserved locally, and like t(-1), if momentum is not conserved by the driving. A simple scaling argument supports the observed long-time tails.
Collapse
Affiliation(s)
- Andrea Fiege
- Georg-August-Universität Göttingen, Institut für Theoretische Physik, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany
| | | | | |
Collapse
|
25
|
Otsuki M, Hayakawa H. Spatial correlations in sheared isothermal liquids: from elastic particles to granular particles. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 79:021502. [PMID: 19391750 DOI: 10.1103/physreve.79.021502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2008] [Revised: 12/12/2008] [Indexed: 05/27/2023]
Abstract
Spatial correlations in sheared isothermal liquids for both elastic and granular cases are theoretically investigated. Using the generalized fluctuating hydrodynamics, correlation functions for both the microscopic scale and the macroscopic scale are obtained. We find the existence of long-range correlations obeying power laws. The validity of our theoretical predictions has been verified from molecular-dynamics simulation.
Collapse
Affiliation(s)
- Michio Otsuki
- Yukawa Institute for Theoretical Physics, Kyoto University, Kitashirakawaoiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan
| | | |
Collapse
|
26
|
Marone C, Carpenter BM, Schiffer P. Transition from rolling to jamming in thin granular layers. PHYSICAL REVIEW LETTERS 2008; 101:248001. [PMID: 19113670 DOI: 10.1103/physrevlett.101.248001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2008] [Indexed: 05/27/2023]
Abstract
We study the granular jamming transition for sheared layers of spherical beads ranging in thickness from 1 to 3 times the grain diameter d. As the layer thickness increases slightly above d, the measured friction jumps discontinuously from 0.02 to >0.1, marking the transition from rolling to jamming. Above a critical layer thickness for jamming, the effective granular pressure displays a power law increase with thickness. For thin layers, friction and P increases as the packing fraction decreases near the jamming transition, in contrast to expectations for bulk granular matter.
Collapse
Affiliation(s)
- C Marone
- Department of Geosciences and Energy Institute Center for Geomechanics, Geofluids, and Geohazards, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
| | | | | |
Collapse
|
27
|
Staron L. Correlated motion in the bulk of dense granular flows. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2008; 77:051304. [PMID: 18643063 DOI: 10.1103/physreve.77.051304] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2007] [Revised: 02/14/2008] [Indexed: 05/26/2023]
Abstract
Numerical simulations of two-dimensional stationary dense granular flows are performed. We check that the system obeys the h_{stop} phenomenology. Focusing on the spatial correlations of the instantaneous velocity fluctuations of the grains, we give evidence of the existence of correlated motion over several grain diameters in the bulk of the flow. Investigating the role of contact friction and restitution, we show that the associated typical length scale lambda is essentially independent of the grain properties. Moreover, we show that lambda is not controlled by the packing compacity. However, in agreement with previous experimental work, we observe that the correlation length decreases with the shear rate. Computing the flows inertia number I , we show a first-order dependence of lambda on I .
Collapse
Affiliation(s)
- Lydie Staron
- CNRS-Université Paris VI, Institut Jean Le Rond d'Alembert, 4 place Jussieu, Paris 75252 Cedex 5, France
| |
Collapse
|