We present a contact dynamics (CD) approach to the Granular Element Method (GEM) Andrade et al. (2012) [1], abbreviated here as CD–GEM. By combining particle shape flexibility through Non-Uniform Rational Basis Splines, properties of implicit time-integration discretization (e.g., larger time steps) and non-penetrating constraints, as well as a reduction to a static formulation in the limit of ...

The aim of this study is to develop a Discrete Element Model (DEM) capable of simulating the main shot peening (SP) processes of industrial interest. By means of this model, shot shot interaction, shot target interaction and the overall shot flow were investigated in detail with limited computational effort. A new technique to dynamically change the coefficient of restitution (CoR) for repeated...

This paper proposes a new approach for the analysis of shear-induced volume change of granular materials. Following a revisit to the micro-mechanical deformation mechanism and the ˆndings from discrete element method simulations, it is concluded that the double slip-rotation rate mechanism is appropriate for the description of granular materials subjected to shear. The implementation of energy ...

A micromechanical study is made of the relationship between interparticle friction coefficient and macroscopic continuum friction and dissipation in idealised granular materials, using Discrete Element Method simulations with varying . As expected, macroscopic friction and dilatancy increase with . Surprisingly, dissipation is present even when or when . Hence, dissipation in idealised granular...

One of the most common methods to measure soil mechanical properties (namely cohesion and internal friction angle) is direct shear box test. In this paper the development of a three-dimensional (3D) discrete element soil model for simulation of a cohesive soil’s direct shear test is presented. The aim was to calibrate the properties of the Hertz-Mindlin with bonding contact model available in E...

Using DEM (Discrete Element Method), a model is presented to simulate the breakage of two-dimensional polygonshaped particles. In this model, shapes of the particles generated after breakage are predefined and each uniform (uncracked) particle is replaced with smaller inter-connected sub-particles. If the bond between these sub-particles breaks, breakage will happen. With the help of this model...

This paper presents a solution for the detection and control of coal loads that is more accurate and convenient than those currently used. To date, no research has addressed the use of a grinding medium as the controlled parameter. To improve the accuracy of the coal load detection based on the kinetic energy of balls in a tubular ball mill, a Discrete Element Method (DEM) model for ball kinema...

We present a reduced formulation for the elastoacoustic scattering problem. The modeling is based on the On Surface Radiation Condition method. It leads to a discrete system which solution is assessed when using Discontinuous Finite Elements.

This paper investigates the effects of chemical reaction and radiation on an unsteady transient MHD free convective and heat transfer of a viscous, incompressible and electrically conducting fluid past a suddenly started infinite vertical porous plate taking into account and the viscous dissipation is presented. Assuming the medium to be non scattered and the fluid to be non gray, emitting abso...