Sökning: "Discrete element methods DEM"

Visar resultat 1 - 5 av 11 avhandlingar innehållade orden Discrete element methods DEM.

1. 1. Strength and deformability of fractured rocks

   Författare :Majid Noorian-Bidgoli; Lanru Jing; John A. Hudson; KTH; []
   Nyckelord :Fractured crystalline rocks; Numerical experiments; Discrete element methods DEM ; Discrete fracture network DFN ; Representative elementary volume REV ; Coupled hydro-mechanical processes; Anisotropy; Effective stress; Failure criteria; Stochastic realizations; Land and Water Resources Engineering; Mark- och vattenteknik;

   Sammanfattning : This thesis presents a systematic numerical modeling framework to simulate the stress-deformation and coupled stress-deformation-flow processes by performing uniaxial and biaxial compressive tests on fractured rock models with considering the effects of different loading conditions, different loading directions (anisotropy), and coupled hydro-mechanical processes for evaluating strength and deformability behavior of fractured rocks. By using code UDEC of discrete element method (DEM), a series of numerical experiments were conducted on discrete fracture network models (DFN) at an established representative elementary volume (REV), based on realistic geometrical and mechanical data of fracture systems from field mapping at Sellafield, UK. LÄS MER

3. 2. Peak Shear Strength of Rock Joints – Towards a Methodology for Prediction Based on Field Data

   Författare :Francisco Ríos Bayona; Fredrik Johansson; Diego Mas Ivars; Stefan Larsson; José Muralha; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Rock joints; peak shear strength; DEM; matedness; aperture; Bergssprickor; skjuvhållfasthet; DEM; sprickans passning; sprickvidd; Jord- och bergmekanik; Soil and Rock Mechanics;

   Sammanfattning : The rock joint shear strength at field scale is an important design parameter and remains a challenge for rock mechanics engineers. In Sweden, there exist a large number of concrete dams that are founded on rock masses which in many cases contain sub-horizontal rock joints. LÄS MER

4. 3. Particle Methods for Modelling Granular Material Flow

   Författare :Simon Larsson; Pär Jonsén; Hans-Åke Häggblad; Gustaf Gustafsson; Eugenio Oñate; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

   Sammanfattning : Granular materials are very abundant in nature and are often used in industry, wherethe dynamics of granular material ow is of relevance in many processes. There arestrong economic and environmental incentives for increased eciency in handling andtransporting granular materials. LÄS MER

5. 4. Accelerated granular matter simulation

   Författare :Da Wang; Martin Servin; Jin Ooi; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; discrete element method; nonsmooth contact dynamics; multibody dynamics; granular media; simulation; projected Gauss-Seidel; validation; iron ore pellets; pelletising balling circuit; model reduction; design optimization;

   Sammanfattning : Modeling and simulation of granular matter has important applications in both natural science and industry. One widely used method is the discrete element method (DEM). It can be used for simulating granular matter in the gaseous, liquid as well as solid regime whereas alternative methods are in general applicable to only one. LÄS MER

7. 5. Experiments and simulations on the mechanics of ice and snow

   Författare :Hassan Bahaloohoreh; Johan Casselgren; Simon Larsson; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Experiments; Sintering force; Capillar bridge; liquid film; Discrete Element Method; Particles; Experimentell mekanik; Experimental Mechanics;

   Sammanfattning : In this study, experiments and simulations were conducted to investigate ice and snow. The ice sintering force as a function of temperature, pressing force (contact load), contact duration, and particle size during the primary stage of sintering was formulated using experimental methods along with an approximate, semi-analytic, close-form solution. LÄS MER