Sökning: "Multiscale convergence"

Visar resultat 11 - 15 av 27 avhandlingar innehållade orden Multiscale convergence.

1. 11. Multiscale methods for simulation of paper making

   Författare :Gustav Kettil; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Paper making; Numerical upscaling; Lay down simulations; Virtual paper sheets; Fiber network model; Forming fabric flow; Fiber suspension flow; Fiber-fiber interaction; Multiscale methods; Fluid structure interaction;

   Sammanfattning : In this work, multiscale methods for simulation of paper making are developed. The emphasis is on simulation of the paper forming process and simulation of the mechanical properties of paper sheets. To simulate paper forming, a novel fiber-fiber interaction method is proposed. LÄS MER

3. 12. Beam-to-Beam Contact and Its Application to Micromechanical Simulation of Fiber Networks

   Författare :Hamid Reza Motamedian; Artem Kulachenko; Umberto Perego; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fiber network; beam-to-beam contact; rotational contact; non-consistent; simulation; finite element; multiscale; microscale; micromechanics; paper; refining; beating; fine; hygroexpansion; shrinkage; drying; Hållfasthetslära; Solid Mechanics;

   Sammanfattning : This doctoral thesis covers the topic of modeling the three-dimensional fiber net- works with the finite element method. It contains the part addressing the numerical aspects of the modeling, namely, the contact formulation and application of the developed methods to the fundamental questions such as the effect of randomness in fiber properties and effect of fines and hygroexpansion. LÄS MER

4. 13. Multiscale modeling of ductile fracture in solids

   Författare :Erik Svenning; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : Ductile fracture occurs in many situations of engineering relevance, for example metal cutting and crashworthiness applications, where the fracture process is important to understand and predict. Increased understanding can be gained by using multiscale modeling, where the effective response of the material is computed from microscale simulations on Statistical Volume Elements (SVEs) 1 containing explicit models for the nucleation and propagation of microscopic cracks. LÄS MER

5. 14. Multiscale and multilevel methods for porous media flow problems

   Författare :Fredrik Hellman; Axel Målqvist; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Beräkningsvetenskap med inriktning mot numerisk analys; Scientific Computing with specialization in Numerical Analysis;

   Sammanfattning : We consider two problems encountered in simulation of fluid flow through porous media. In macroscopic models based on Darcy's law, the permeability field appears as data.The first problem is that the permeability field generally is not entirely known. LÄS MER

7. 15. Mathematical analysis and approximation of a multiscale elliptic-parabolic system

   Författare :Omar Richardson; Adrian Muntean; Alfred Schmidt; Karlstads universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Two-scale modelling; two-scale Galerkin approximation; inverse Robin estimates; elliptic-parabolic system; a priori analysis; a posteriori error estimators; Matematik; Mathematics;

   Sammanfattning : We study a two-scale coupled system consisting of a macroscopic elliptic equation and a microscopic parabolic equation. This system models the interplay between a gas and liquid close to equilibrium within a porous medium with distributed microstructures. We use formal homogenization arguments to derive the target system. LÄS MER