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Showing 1 to 20 of 25 for “"discrete element modeling"”.
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Discrete Element Modeling of Granular Flows in Vibrationally-fluidized Beds
… For such a system, it was decided that a discrete element method (DEM) was the most appropriate tool to model bulk velocity and circulation of media. In the first phase of the work, a vibratory finisher was modified to introduce planar vibration into a single layer of particles. The motion …
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A distributed discrete element modeling environment : algorithms, implementation and applications
Thesis (Sc. D.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1996.
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Discrete Element Modeling of Railway Ballast for Studying Railroad Tamping Operation
The development of Discrete Element Model (DEM) of railway ballast for the purpose of studying the behavior of ballast particles during tamping is addressed in a simulation study, with the goal of optimizing the railroad tamping operation. A comprehensive literature review of applicability of DEM …
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Discrete Element Modeling of Railway Ballast for Studying Railroad Tamping Operation
… by developing a simulation model using the Discrete Element Model (DEM), with the aim of optimizing the railroad tamping operation. A comprehensive literature review is presented showcasing the applicability of DEM techniques in modeling ballast behavior and its feasibility in studying the …
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Discrete element modeling of railroad ballast using imaging based aggregate morphology characterization
… remain unknown. In previous designs and modeling practices, railroad ballast has usually been treated as a homogeneous and continuous layer. This approach is not suitable to model the deformation behavior of the particulate nature railroad ballast aggregates under dynamic moving loads. …
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Asphalt mixture evaluation using performance space diagrams, digital image correlation, and discrete element modeling
… with heterogeneous numerical simulations via modeling tools such as the discrete element method (DEM). However, there has not been an analysis method developed using traditional high and low temperature laboratory mixture test data to identify shifts in performance. Furthermore, little …
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Integrating Laser Scanning with Discrete Element Modeling for Improving Safety in Underground Stone Mines
… the past years, have allowed numerical modeling codes to represent more realistically the behavior of a fractured rock masses. This work presents and implements a methodology that integrates laser scanning technology along with Discrete Element Modeling as tools for characterizing, …
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Discrete element modeling of the influences of density and confining pressure on the compression and shear behavior of granular materials
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1998.
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A GPGPU implementation of the discrete element method applied to modeling the dynamic particulate environment inside a tumbling mill
… a century. With the advent of better computing, discrete element modeling (DEM) has taken on the challenge to model the dynamic particulate environment inside these devices in the search for understanding and hence improving the process of the size reduction of ore. This process represents a …
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Investigation of efficient geometric shape algorithms for numerical simulation of discrete particle systems
The efficiency of a discrete particle simulation implementation relies on several factors, including the geometric representation, contact resolution, and neighbor-sorting algorithm used. The focus here is on the first two of this list: the geometric representation and the corresponding contact …
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On the shear strength of polyurethane coated railroad ballast
… of the limestone samples. An image aided discrete element modeling approach was used to simulate the shear box tests and calculate number of particle contacts and sample porosities for both the granite and limestone gradations. The simulation results showed that even though the di erences …
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Analytical and Numerical Techniques for the Optimal Design of Mineral Separation Circuits
… was implemented into a dynamic physics-based discrete element modeling environment. The virtual experiment was used to quantify the selectivity of each circuit configuration, and the final results validate the initial circuit analysis projections.
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Force Chain Detection in Unconsolidated Sands
… initial application of the model will utilize discrete element modeling approach to simulate the force chain network of the sand pack and predict its behavior under further stress loading. The model will allow to extract the statistics and the distribution of the stress across the calculated …
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Investigation of fluidized bed systems using coupled DEM-CFD framework
… Capturing this multiphase phenomenon requires modeling strategies that possess good fidelity over a range of scales. Discrete Element Modeling (DEM) coupled with Computational Fluid Dynamics (CFD) provides a good platform to analyze the complex coupled multiphase hydrodynamics inside fluidized …
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Self-calibrating mass flow sensor
… were further verified using data collected from discrete element modeling simulations, and experimental data collected in two fashions: using a full-scale replica of the mass flow sensing system, and using a small-scale, benchtop testing apparatus. Furthermore, the ability of the developed …
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A Risk-Based Pillar Design Approach for Improving Safety in Underground Stone Mines
… mapping process was used to generate discrete fracture networks (DFNs) for each discontinuity set. The Discrete Element Modeling Software 3DEC was used along with the DFNs to simulate fractured rock pillars. Different fractured pillar strength modeling approaches were evaluated, and …
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Numerical and experimental evaluation of the erodibility of particle packings with surface treatments and spring reinforcements using the discrete element method
… of physical flume experiments and the discrete element method (DEM). Packings composed of spherical glass particles, with and without surface treatments and angled at two different slopes, were tested experimentally and simulated numerically under surficial flow conditions. The surface …
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Study of the heating and ignition of metal powder by electrostatic discharge
… simulating packing of polydisperse powders using Discrete Element Modeling. In the model, the electrical resistance network created by particle contacts is analyzed to determine the powder impedance and energy distribution among heated particles. The model is calibrated for Al powders by matching …
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Mechanisms of fracture complexity and topology of fracture systems induced by hydraulic fracturing
… induced fracture systems show the necessity of modeling fracture complexity for improving completion design and interpreting drained reservoir volume (DRV). Thus, this work explains the mechanisms of HF-NF interaction and provides a physics-based method to infer SRV. First, fracture complexity …
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Mathematical model for improved mass flow estimation in the feeder housing of a forage harvester
… various material compaction models, and discrete element method simulations. When tested with experimental data, the model performed better than the current sensor system for some parameter sets, and as well as the current sensor system for others. Because of the mathematical complexity …
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