Article
Engineering, Geological
Xiaogang Guo, Chong Peng, Wei Wu, Yongqi Wang
Summary: This study proposes a unified constitutive model for granular-fluid material, applicable to quasi-static and dense flow regimes. By considering the main intergranular interactions and granular-fluid interactions, as well as utilizing the Mohr-Coulomb model and a Bagnold-type relation, control over mechanical behaviors is achieved. Analytical solutions are obtained for dry granular flows in various configurations, providing new insights into dense granular flow behavior.
Article
Mechanics
G. C. Yang, Y. J. Huang, Y. Lu, C. Y. Kwok, Y. D. Sobral, Q. H. Yao
Summary: This research treats granular materials as a continuum and uses the lattice Boltzmann method to simulate their flow behavior. A novel frictional boundary condition is introduced to accurately describe the stick-slip phenomenon at the boundaries. The numerical model shows good agreement with analytical solutions and can predict various granular flow scenarios.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
T. Trewhela, C. Ancey, J. M. N. T. Gray
Summary: Particles of differing sizes are prone to segregation in shear driven flows, affecting industrial processes and hazardous geophysical mass flows. Refractive-index matched oscillatory shear-cell experiments have identified a unifying scaling law for segregation velocity in extreme cases.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Engineering, Chemical
Moyu Yang, Ran Li, Yingnan Xiu, Qiang Zeng, Xiaoyan Ye, Hui Yang
Summary: Through experiments and DEM simulations, it is found that a ring-shaped region named Quasi-static Region exists between the particles expanding outward and collapsing inward during the impact process. Quasi-static Region is always generated from the impact point simultaneously and propagates at a uniform speed. The velocity of particles in the particle extend region varies linearly in space and time during the propagation of Quasi-static Region, and the change rate is only related to the properties of the particle system. The simulation results show that the particle flow in Quasi-static Region is elastic-inertial flow, while the particle flow expanding outward and collapsing inward is inertial flow.
Article
Physics, Multidisciplinary
Kasra Farain, Daniel Bonn
Summary: The question of when dense granular materials start to flow under stress has not been resolved. A simple equation based on frictional aging of the granular packing is developed and tested, resulting in a nonmonotonic stress-strain relation independent of shear rate. This relation helps understand the quasistatic deformations and solid-to-liquid transition of aging granular media. It also explains the flow history dependence of mechanical properties and sensitivity to initial preparation of granular media.
PHYSICAL REVIEW LETTERS
(2023)
Article
Mechanics
Teng Man, Zaohui Zhang, Herbert E. E. Huppert, Sergio A. A. Galindo-Torres
Summary: This paper investigates granular column collapses using the sphero-polyhedral discrete element method, and proposes a new effective initial aspect ratio to unify the description of the relative run-out distances of bi-frictional granular mixtures. The study also finds that deviations from classical power-law scaling in both the dimensionless terminal time and the dimensionless time when the system reaches the maximum kinetic energy may result from differences in the initial solid fraction and initial structures. To clarify the influence of initial states, the authors decrease the initial solid fraction and propose a trial function to quantitatively describe its influence.
JOURNAL OF FLUID MECHANICS
(2023)
Article
Mechanics
Peter Varun Dsouza, Prabhu R. Nott
Summary: Granular materials exhibit unique features such as dilatancy and large-scale secondary flow driven by a combination of shear and gravity. The height at which the material is filled in a primary flow determines both the shape of the shearing region and the form of the secondary flow, indicating a close coupling between the two phenomena. Unlike fluid instabilities driven by inertia, the secondary flow in granular materials occurs at low shear rates and is an integral part of the kinematic response.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Multidisciplinary Sciences
Dmitry Puzyrev, David Fischer, Kirsten Harth, Torsten Trittel, Raul Cruz Hidalgo, Eric Falcon, Martial Noirhomme, Eric Opsomer, Nicolas Vandewalle, Yves Garrabos, Carole Lecoutre, Fabien Palencia, Ralf Stannarius
Summary: Studying the dynamics of granular multiparticle ensembles requires optical analysis methods. Numerical simulations similar to experiments can be used to validate the reliability of analysis methods. This approach not only confirms the accuracy of simulations, but also tests the applicability of visual analysis.
SCIENTIFIC REPORTS
(2021)
Article
Materials Science, Multidisciplinary
Andrew Hong, Aaron Morris
Summary: Extending the DSMC method to moderately dense granular flows demands recovering collisional pressures. While some DSMC variants successfully recover the non-ideal equation of state, they are mainly validated for systems with a homogeneous solids fraction field. Systems with strong density gradients, such as granular clustering, are rarely investigated due to the numerical phenomenon of overpacking.
Article
Engineering, Chemical
J. Krzyzanowski, J. Tejchman, W. Solowski, M. Wojcik
Summary: This paper focuses on the confined flow of cohesionless sand in a silo using the material point method (MPM). Different initial void ratios and wall roughness were considered in the simulations, with emphasis on the evolution of shear zones and their impact on wall stresses during flow. The numerical findings enhance the understanding of shear localization in granular materials and its effects on wall pressures in confined silo flow.
Article
Computer Science, Interdisciplinary Applications
A. Grabowski, M. Nitka, J. Tejchman
Summary: The paper investigates the quasi-static confined flow of cohesionless sand in a plane strain model silo through numerical modelling using the discrete element method. By comparing DEM simulation outcomes with experimental and theoretical solutions, the study focuses on the formation and evolution of wall and internal shear zones during sand flow, as well as the impact of particle displacements, rotations, contact forces, void ratios, and wall stresses.
COMPUTERS AND GEOTECHNICS
(2021)
Article
Mechanics
Kaushik Balakrishnan, Josette Bellan
Summary: The study investigates the influence of atmospheric density and jet-fluid density on supersonic jet-induced cratering on a granular particle bed using large eddy simulation coupled with a granular flow model. Results show that the crater cross-sectional shapes, depth, and ejecta amount depend on the ratio between jet-fluid density and atmospheric density. Conical craters are deeper, have smaller diameters, and more ejecta compared to parabolic craters, which are shallower with larger diameters and subdued ejecta.
JOURNAL OF FLUID MECHANICS
(2021)
Review
Chemistry, Physical
Pierre Rognon, Matthew Macaulay
Summary: This article introduces the diffusion process induced by shear deformation in granular materials, focusing on dense flows. It presents the established scaling laws for continuum diffusivity and their relation to the micro-mechanisms of granular random walk, suggesting how this knowledge may advance understanding of granular rheology and diffusion in other soft materials.
Article
Mechanics
Ishan Srivastava, Leonardo E. Silbert, Gary S. Grest, Jeremy B. Lechman
Summary: This study investigates the flow of dense granular materials under external shear stress and pressure using discrete element method simulations, proposing a rheological model to describe the two types of flow. The simulations show viscometric behavior with non-negligible first and second normal stress differences, highlighting the role of contact fabric tensor and strain rate tensor in determining normal stress differences.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Mechanics
Laurent Lacaze, Joris Bouteloup, Benjamin Fry, Edouard Izard
Summary: This study investigates the collapse of a granular column in a liquid using numerical simulations, focusing on the influence of Stokes number St and the initial volume fraction phi(i) on the dynamics of the collapse. A dedicated numerical model with a discrete element method is used to provide a comprehensive description of the granular phase in dense granular flows. The research aims to characterize the dynamics of the collapse and its final deposit in relation to (St, phi(i)), as well as to describe the granular rheology and dilatancy effects based on these two dimensionless numbers.
JOURNAL OF FLUID MECHANICS
(2021)
Article
Geosciences, Multidisciplinary
Federico Riva, Federico Agliardi, David Amitrano, Giovanni B. Crosta
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2018)
Article
Materials Science, Multidisciplinary
Chi-Cong Vu, Jerome Weiss, Olivier Ple, David Amitrano, Damien Vandembroucq
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2018)
Article
Multidisciplinary Sciences
Jerome Weiss, Lucas Girard, Florent Gimbert, David Amitrano, Damien Vandembroucq
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2014)
Article
Physics, Multidisciplinary
Chi-Cong Vu, David Amitrano, Olivier Ple, Jerome Weiss
PHYSICAL REVIEW LETTERS
(2019)
Article
Geochemistry & Geophysics
Jean-Luc Got, David Amitrano, Ioannis Stefanou, Elodie Brothelande, Aline Peltier
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2019)
Article
Geosciences, Multidisciplinary
G. Le Roy, A. Helmstetter, D. Amitrano, F. Guyoton, R. Le Roux-Mallouf
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2019)
Article
Construction & Building Technology
Chi-Cong Vu, Olivier Ple, Jerome Weiss, David Amitrano
CONSTRUCTION AND BUILDING MATERIALS
(2020)
Article
Construction & Building Technology
Chi-Cong Vu, Jerome Weiss, Olivier Ple, David Amitrano
Summary: Concrete's elastic properties are independent of concrete mixtures and sample sizes, while the compressive strength is influenced by sample sizes. There is no direct proportionality between the linear property of elastic modulus and the non-linear property of compressive strength in concrete. Using empirical expressions from building codes to estimate elastic modulus from compressive strength can lead to incorrect designs.
MATERIALS AND STRUCTURES
(2021)
Article
Geochemistry & Geophysics
Axel Periollat, Mathilde Radiguet, Jerome Weiss, Cedric Twardzik, David Amitrano, Nathalie Cotte, Lou Marill, Anne Socquet
Summary: In this study, the authors analyze GPS data to investigate the deformation following the Tohoku-Oki megathrust earthquake. They find that the early stage of the postseismic phase is mainly influenced by afterslip and transient brittle creep mechanisms. The study highlights the importance of understanding the role of different mechanisms in deciphering the complexities of postseismic deformation.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Multidisciplinary Sciences
Chi-Cong Vu, Jerome Weiss, Olivier Ple, David Amitrano
Article
Physics, Fluids & Plasmas
Kamran Karimi, David Amitrano, jerome Weiss
Article
Physics, Fluids & Plasmas
David Amitrano, Lucas Girard
Article
Physics, Multidisciplinary
Roland Lehoucq, Jerome Weiss, Berengere Dubrulle, Axelle Amon, Antoine Le Bouil, Jerome Crassous, David Amitrano, Francois Graner
FRONTIERS IN PHYSICS
(2015)
Article
Physics, Multidisciplinary
Ki-Young Choi, Jihn E. Kim, Bumseok Kyae
FRONTIERS IN PHYSICS
(2015)
Article
Geography, Physical
Floriane Provost, Jean-Philippe Malet, Clement Hibert, Agnes Helmstetter, Mathilde Radiguet, David Amitrano, Nadege Langet, Eric Larose, Claudia Abanco, Marcel Hurlimann, Thomas Lebourg, Clara Levy, Gaelle Le Roy, Patrice Ulrich, Maurin Vidal, Benjamin Vial
EARTH SURFACE DYNAMICS
(2018)