Sökning: "discrete particle model"

Visar resultat 11 - 15 av 55 avhandlingar innehållade orden discrete particle model.

1. 11. Discrete element technique for modeling high-speed railway tracks

   Författare :Alireza Ahmadi; Stefan Larsson; Carl Wersäll; Liang Cui; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Polygonal particles; Direct shear test; Particle scaling; Bal- lasted track; DEM; Polygonala partiklar; direkt skjuvförsök; partikelskalning; ballastspår; DEM; Soil and Rock Mechanics; Jord- och bergmekanik;

   Sammanfattning : The Discrete element method (DEM) is a methodology to investigatethe interactions among granular materials. It analyzes the behavior of par-ticulate environments by solving force-displacement equations that adhereto Newton’s second law of motion. LÄS MER

3. 12. Numerical study of dense particle flows under planar shear

   Författare :Junhao Dong; Beräkningskemi; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dense suspension; granular flow; shear thickening; oscillatory flow; rheology; Discrete element method;

   Sammanfattning : In this thesis I conducted numerical simulations to study the flow behavior of dense particle flows composed of hard particles under planar shear using the discrete element method. The simulations were carried out in two dimensional systems, where the particles are modelled as circular discs. The discs are non-Brownian and neutrally buoyant. LÄS MER

4. 13. Surface complexation in natural particle suspensions

   Författare :Qing Du; Luleå tekniska universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry of Interfaces; Gränsytors kemi;

   Sammanfattning : This thesis is a summary of our studies on (i) the proton and copper adsorption at aqueous illite surfaces, (ii) the proton and copper complexation of humic substances (fulvic acid FA and humic acid HA), (iii) the interaction between illite and fulvic acid, and (iv) the copper complexation behaviors in illite-FA bi-complexant systems. These particular studies were designed to help us develop a framework for modelling heavy metal complexation/adsorption mechanisms at natural particle surfaces. LÄS MER

5. 14. Flow and Compression of Granulated Powders : The Accuracy of Discrete Element Simulations and Assessment of Tablet Microstructure

   Författare :Ann-Sofie Persson; Göran Frenning; Göran Alderborn; Marie Wahlgren; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Discrete Element Method; Granule; Flow; Angle of Repose; Discharge Rate; Shear; Rolling friction; Compression; Elastic deformation; Microstructure; Degree of compression; Tensile strength; Galenisk farmaci; Pharmaceutics;

   Sammanfattning : Simulations are powerful and important tools for gaining insight into powder processes. Ultimately, simulations have the potential to replace experiments. Thus, accurate models and insight into the essential factors for descriptions of powder behaviour are required. LÄS MER

7. 15. Discrete element simulation of elasto-plastic shock waves in high-velocity compaction

   Författare :Muhammad Shoaib; Leaf Kari; Bruska Azhdar; Wim Desmet; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; High-velocity compaction; Discrete element method; Plastic deformaiton; dynaimic loading; elasto-plastic shock wave; Friction; Adhesion; Physics; Fysik; Järnvägsgruppen - Ljud och vibrationer; Järnvägsgruppen - Ljud och vibrationer;

   Sammanfattning : Elasto-plastic shock waves in high-velocity compaction of spherical metal particles are the focus of this thesis which consists of four papers (A-D). The compaction process is modeled by a discrete element method while using elastic and plastic loading, elastic unloading and adhesion at contacts. LÄS MER