Sökning: "flow stress"

Visar resultat 16 - 20 av 451 avhandlingar innehållade orden flow stress.

  1. 16. Explicit algebraic subgrid-scale stress and passive scalar flux modeling in large eddy simulation

    Författare :Amin Rasam; Arne V. Johansson; Shia-Hui Peng; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulence; Large eddy simulation; explicit algebraic subgrid-scale model; passive scalar; stochastic modeling; backscatter; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : The present thesis deals with a number of challenges in the field of large eddy simulation (LES). These include the performance of subgrid-scale (SGS) models at fairly high Reynolds numbers and coarse resolutions, passive scalar and stochastic modeling in LES. LÄS MER

  3. 17. The flow of pulp suspensions

    Författare :Helena Fock; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Pulp suspensions; Velocity profile; Concentration profile; Wall layer; Particle image velocimetry; Flow behaviour; Computational fluid dynamics; Ultrasound velocity profiling;

    Sammanfattning : Large quantities of pulp suspensions are handled in the pulp and paper industry and knowledge of their flow behaviour is very important in the design and operation of process equipment. Despite this, there is still a lack of a fundamental understanding of the mechanisms of the pulp suspension flow. LÄS MER

  4. 18. Turbulence modeling of compressible flows with large density variation

    Författare :Igor Grigoriev; Arne Johansson; Stefan Wallin; Geert Brethouwer; Stefan Hickel; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulence; DRSM; EARSM; active scalar; compressible flow; reacting flow; supercritical flow; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : In this study we highlight the influence of mean dilatation and mean density gradient on the Reynolds stress modeling of compressible, heat-releasing and supercritical turbulent flows.Firstly, the modeling of the rapid pressure-strain correlation has been extended to self-consistently account for the influence of mean dilatation. LÄS MER

  5. 19. Rheology of cement grout  : Ultrasound based in-line measurement technique and grouting design parameters

    Författare :Mashuqur Rahman; Stefan Larsson; Ulf Håkansson; Olafur Wallevik; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; grouting; grouting design; cement grout; Bingham number; shear rate; plug flow; thixotropy; yield stress; in-line rheology; UVP PD; Flow-Viz; viscosity bifurcation; aging; off-line rheometry; pump characteristics; Civil and Architectural Engineering; Byggvetenskap;

    Sammanfattning : Grouting is performed in order to decrease the permeability and increase the stiffness of the material, especially soil and rock. For tunnelling and underground constructions, permeation grouting is done where cement based materials are pumped inside drilled boreholes under a constant pressure, higher than the ground water pressure. LÄS MER

  7. 20. The Underground as a Storage Facility. Modelling of Nuclear Waste Repositories and Aquifer Thermal Energy Stores

    Författare :Thomas Probert; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; exponential decay; modelling; fractured rock; classical mechanics; quantum mechanics; Mathematical and general theoretical physics; relativity; statistical physics; thermodynamics; Matematisk och allmän teoretisk fysik; klassisk mekanik; relativitet; kvantmekanik; gravitation; statistisk fysik; termodynamik; Environmental technology; pollution control; kontroll av utsläpp; Miljöteknik; conformal flow; heat as a tracer; KBS-3; stress field; temperature field; analytical solution; salt buoyancy; groundwater flow; nuclear waste repository; aquifer thermal energy storage; Fysicumarkivet A:1998:Probert;

    Sammanfattning : The underground is a vast region, which is, too a large extent, unused by man. It has a large potential as a storage facility due to its vastness and availability. This thesis, which consists of eleven papers and reports, deals with nuclear waste repositories in solid rock and with aquifer thermal energy storage systems. LÄS MER