Experimental and Numerical Study of Humid Granular Material

Experimental and Numerical Study of Humid Granular Material PDF Author: Haithem Louati
Publisher:
ISBN:
Category :
Languages : en
Pages : 141

Get Book Here

Book Description
We study experimentally and numerically the shear behaviour of wet granular material. We investigate the effect of the liquid content and the applied normal stresses to this behaviour. An annular shear cell was used to carry out the experiments, for a large range of applied normal stress from about 0.3 kPa to 12 kPa. The results give the variation of the shear stress at steady-state as a function of the normal stress for a wide range of liquid fraction. The incorporated liquid goes from forming bridges at the contact point to completely filling the space between grains. The shear resistance and the voidage fraction variations with the liquid fraction were analysed. Depending on the applied normal stress and the liquid fraction, different regimes of the shear resistance were identified. The discrete element method (DEM) was used to gain a microscopic understanding of the shear behaviour of dry and partially wet granular material in the shear cell. Large size glass beads were used to speed up the computational time and to facilitate characterisation at the particle scale. First, the influence of the microscopic properties of the particle (The Young's modulus and the sliding friction) on the macroscopic properties of dry and wet granular materials (the coordination number, the voidage fraction, the shear ratio and the velocity of particles) was investigated. Secondly, the shear behaviour of the partially wet granular material for different liquid fractions and normal stresses was studied. The capillary forces and the number of liquid bridges were quantitatively analysed.

Experimental and Numerical Study of Humid Granular Material

Experimental and Numerical Study of Humid Granular Material PDF Author: Haithem Louati
Publisher:
ISBN:
Category :
Languages : en
Pages : 141

Get Book Here

Book Description
We study experimentally and numerically the shear behaviour of wet granular material. We investigate the effect of the liquid content and the applied normal stresses to this behaviour. An annular shear cell was used to carry out the experiments, for a large range of applied normal stress from about 0.3 kPa to 12 kPa. The results give the variation of the shear stress at steady-state as a function of the normal stress for a wide range of liquid fraction. The incorporated liquid goes from forming bridges at the contact point to completely filling the space between grains. The shear resistance and the voidage fraction variations with the liquid fraction were analysed. Depending on the applied normal stress and the liquid fraction, different regimes of the shear resistance were identified. The discrete element method (DEM) was used to gain a microscopic understanding of the shear behaviour of dry and partially wet granular material in the shear cell. Large size glass beads were used to speed up the computational time and to facilitate characterisation at the particle scale. First, the influence of the microscopic properties of the particle (The Young's modulus and the sliding friction) on the macroscopic properties of dry and wet granular materials (the coordination number, the voidage fraction, the shear ratio and the velocity of particles) was investigated. Secondly, the shear behaviour of the partially wet granular material for different liquid fractions and normal stresses was studied. The capillary forces and the number of liquid bridges were quantitatively analysed.

An Experimental and Numerical Study of the Effect of Microstructure on Wave Propagation Phenomena in Granular Media

An Experimental and Numerical Study of the Effect of Microstructure on Wave Propagation Phenomena in Granular Media PDF Author: Changyi Zhu
Publisher:
ISBN:
Category : Granular materials
Languages : en
Pages : 338

Get Book Here

Book Description


Powders and Grains 2005, Two Volume Set

Powders and Grains 2005, Two Volume Set PDF Author: R. Garcia-Rojo
Publisher: Taylor & Francis
ISBN: 0415889421
Category : Technology & Engineering
Languages : en
Pages : 1512

Get Book Here

Book Description
This volume contains the proceedings of the Fifth International Conference on the Micromechanics of Granular Media, Powders and Grains 2005. Powders and Grains is an international scientific conference held every 4 years that brings together engineers and physicists interested in the micromechanics of granular media.The book is a guide to the hotte

Engineering Applications of Discrete Element Method

Engineering Applications of Discrete Element Method PDF Author: Xuewen Wang
Publisher: Springer Nature
ISBN: 9811579776
Category : Science
Languages : en
Pages : 186

Get Book Here

Book Description
This book introduces the engineering application of the discrete element method (DEM), especially the simulation analysis of the typical equipment (scraper conveyor, coal silos, subsoiler) in the coal and agricultural machinery. In this book, the DEM is applied to build rigid and loose coupling model, and the kinematic effect of the bulk materials, the mechanical effect of the interaction between the bulk materials, and the mechanical equipment in the operation process of the relevant equipment are studied. On this basis, the optimization design strategy of the relevant structure is proposed. This book effectively promotes the application of DEM in engineering, analyzes the operation state, failure mechanism, and operation effect of related equipment in operation, and provides theoretical basis for the optimal design of equipment. The book is intended for undergraduate and graduate students who are interested in mechanical engineering, researchers investigating coal and agricultural machinery, and engineers working on designing related equipments.

A Theoretical and Numerical Study of the Flow of Granular Materials Down an Inclined Plane. Final Report

A Theoretical and Numerical Study of the Flow of Granular Materials Down an Inclined Plane. Final Report PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 48

Get Book Here

Book Description
The mechanics of the flowing granular materials such as coal, agricultural products, at deal of attention as it has fertilizers, dry chemicals, metal ores, etc. have received a great deal of attention as it has relevance to several important technological problems. Despite wide interest and more than five decades of experimental and theoretical investigations, most aspects of the behavior of flowing granular materials are still not well understood. So Experiments have to be devised which quantify and describe the non-linear behavior of the modular materials, and theories developed which can explain the experimentally observed facts. As many models have been suggested for describing the behavior of granular materials, from both continuum and kinetic theory viewpoints, we proposed to investigate the validity and usefulness of representative models from both the continuum and kinetic theory points of view, by determining the prediction of such a theory, in a representative flow, with respect to existence, non-existence, multiplicity and stability of solutions. The continuum model to be investigated is an outgrowth of a model due to Goodman and Cowin (1971, 1972) and the kinetic theory models being those due to Jenkins and Richman (1985) and Boyle and Massoudi (1989). In this report we present detailed results regarding the same. Interestingly, we find that the predictions of all the theories, in certain parameter space associated with these models, are qualitatively similar. This ofcourse depends on the values assumed for various material parameters in the models, which as yet are unknown, as reliable experiments have not been carried out as yet for their determination.

Mathematical Modeling and Numerical Techniques in Drying Technology

Mathematical Modeling and Numerical Techniques in Drying Technology PDF Author: Ian Turner
Publisher: CRC Press
ISBN: 148229219X
Category : Science
Languages : en
Pages : 696

Get Book Here

Book Description
Offers information necessary for the development of mathematical models and numerical techniques to solve specific drying problems. The book addresses difficult issues involved with the drying equations of numerical analysis, including mesh generation, discretinization strategies, the nonlinear equation set and the linearized algebraic system, convergance criteria, time step control, experimental validation, optimum methods of visualization results, and more.

Kinematics and Kinetics of Granular Mixture

Kinematics and Kinetics of Granular Mixture PDF Author: Jiafeng Zhang
Publisher: ProQuest
ISBN: 9781109224511
Category :
Languages : en
Pages : 396

Get Book Here

Book Description
Particle motion in dense granular materials is well-correlated locally, but uncorrelated globally, likely due to the highly dissipative nature of the material. This combination makes predictive modeling difficult, and there is no constitutive model for densely flowing granular materials. On the other hand, the relatively uncorrelated motion often results in highly symmetric system-spanning patterns of well-sorted particles. These patterns appear highly sensitive to the type of particulate mixture. Up to now, no link has been made between the particle properties and the kinematics of the bulk behavior such as velocity, volume fraction and velocity fluctuations. This thesis seeks to understand the bulk behavior of granular mixtures.

Particle Size and Bondary Effects in Rapid Granular Shear Flows : An Experimental and Numerical Study

Particle Size and Bondary Effects in Rapid Granular Shear Flows : An Experimental and Numerical Study PDF Author: Andres D. Orlando
Publisher:
ISBN:
Category : Bulk solids flow
Languages : en
Pages : 174

Get Book Here

Book Description


Unsaturated Soils: Research & Applications

Unsaturated Soils: Research & Applications PDF Author: Nasser Khalili
Publisher: CRC Press
ISBN: 1315749580
Category : Technology & Engineering
Languages : en
Pages : 1872

Get Book Here

Book Description
Unsaturated Soils: Research and Applications contains 247 papers presented at 6th International Conference on Unsaturated Soils (UNSAT2014, Sydney, Australia, 2-4 July 2014). The two volumes provide an overview of recent experimental and theoretical advances in a wide variety of topics related to unsaturated soil mechanics:- Unsaturated Soil Behavi

Coal and rock dynamic disasters: Advances of physical and numerical simulation in monitoring, early warning, and prevention

Coal and rock dynamic disasters: Advances of physical and numerical simulation in monitoring, early warning, and prevention PDF Author: Xuelong Li
Publisher: Frontiers Media SA
ISBN: 2832549837
Category : Science
Languages : en
Pages : 160

Get Book Here

Book Description
With the soaring growth of global population and socioeconomy, energy consumption and demand has been rapidly rising, and coal would still remain a fundamental energy source for a long time into the future. Seeking deep coal resources becomes an inevitable trend due to the depletion of shallow coal resources. Deep mining of coal resources promotes socioeconomic development, whereas bringing a variety of security challenges. In deep underground, there is a significant risk increase in coal and rock dynamic disasters (CRDDs), owing to the changes in physical and mechanical properties of coal and rock. In this regard, it is of great importance and necessity to prevent and control CRDDs effectively and efficiently. As typical natural geological materials, coal and rock have evident inhomogeneity and anisotropy, and manifest differences in strength, deformation, permeability, and other mechanical characteristics due to their various mineral compositions, porosity, and weak structural plane. Considering the complexity of coal and rock, it is essential to carry out laboratory experiments on macroscopic mechanical responses and microscopic fracture characteristics to identify precursor information and reveal evolution mechanisms of dynamic disasters. Yet by far less is known about the combined physical and numerical simulation on multi-scale CRDDs, which hinders the development of corresponding prevention and control technologies. This Research Topic aims to initiate a global scientific and technological discussion on the cutting-edge advances of physical and numerical simulation in monitoring, early warning, and prevention of CRDDs. We welcome Original Research and Review articles addressing the following themes that include, but are not limited to: • Physical and numerical simulation on mechanisms of CRDDs • Numerical simulation on prediction of CRDDs • Numerical simulation on prevention and control of CRDDs collapse