Sökning: "Stokes equation"

Visar resultat 1 - 5 av 84 avhandlingar innehållade orden Stokes equation.

  1. 1. Analytical vortex solutions to Navier-Stokes equation

    Författare :Henrik Tryggeson; Mats Lyberg; Maarten Brons; Växjö universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; conical vortex; Navier-Stokes equation; analytical solution; 2-D vortices; turbulence; vortex ring; stretched vortex; coherent structures; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : Fluid dynamics considers the physics of liquids and gases. This is a branch of classical physics and is totally based on Newton's laws of motion. Nevertheless, the equation of fluid motion, Navier-Stokes equation, becomes very complicated to solve even for very simple configurations. LÄS MER

  3. 2. Homogenization of some new mathematical models in lubrication theory

    Författare :Afonso Fernando Tsandzana; Peter Wall; Lars- Erik Persson; John Fabricius; Anders Holmbom; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; lubrication theory; homogenization theory; Reynolds equation; cavitation; surfaces roughness; Stokes equation; Matematik; Mathematics;

    Sammanfattning : We consider mathematical modeling of thin film flow between two rough surfaces which are in relative motion. For example such flows take place in different kinds of bearings and gears when a lubricant is used to reduce friction and wear between the surfaces. LÄS MER

  4. 3. Finite element procedures for virtual tribology

    Författare :Bertil Nilsson; Göteborgs universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Tribology; Reynolds equation; Stokes equation; cavitation; FEM; adaptivity; variational inequality; penalty formulation; error estima- tion; residual; duality.;

    Sammanfattning : The main purpose of this thesis is to use modern goal-oriented adap- tive finite element techniques in order to improve the numerical simulation of tribology. Two novel adaptive finite element methods for the Reynolds thin film model, and Stokes model including cavitation are presented and their different strategies are compared. LÄS MER

  5. 4. Initial-Boundary-Value Problems for the Stokes and Navier–Stokes Equations on Staggered Grids

    Författare :Jonas Nilsson; Bertil Gustafsson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Stokes equations; Navier-Stokes equations; boundary conditions; staggered grids; higher-order methods; Numerical Analysis; Numerisk analys;

    Sammanfattning : In the first part of the thesis various types of boundary conditions for the steady state Stokes equations are considered. We formulate the boundary conditions in a new way, such that the boundary value problem becomes non-singular, and derive estimates of the solution. LÄS MER

  7. 5. Stress, Flow and Particle Transport in Rock Fractures

    Författare :Tomofumi Koyama; Lanru Jing; Marc Boulon; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Numerical simulation; laboratory experiments; rock fracture; coupled stress-flow-tracer test; shear displacement; fluid flow; particle transport; finite element method FEM ; particle tracking method; Navier-Stokes equation; Reynolds equation; streamline velocity dispersion.; Geoengineering; Geoteknik;

    Sammanfattning : The fluid flow and tracer transport in a single rock fracture during shear processes has been an important issue in rock mechanics and is investigated in this thesis using Finite Element Method (FEM) and streamline particle tracking method, considering evolutions of aperture and transmissivity with shear displacement histories under different normal stresses, based on laboratory tests. The distributions of fracture aperture and its evolution during shear were calculated from the initial aperture fields, based on the laser-scanned surface roughness features of replicas of rock fracture specimens, and shear dilations measured during the coupled shear-flow-tracer tests in laboratory performed using a newly developed testing apparatus in Nagasaki University, Nagasaki, Japan. LÄS MER