Sökning: "large eddy simulation"

Visar resultat 21 - 25 av 173 avhandlingar innehållade orden large eddy simulation.

  1. 21. Anisotropy-resolving subgrid-scale modelling using explicit algebraic closures for large eddy simulation

    Författare :Amin Rasam; Arne Johansson; Bernard Geurts; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulence; large eddy simulation; explicit algebraic subgridscale model; passive scalar; stochastic modelling; periodic hill flow; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : The present thesis deals with the development and performance analysis ofanisotropy-resolving models for the small, unresolved scales (”sub-grid scales”,SGS) in large eddy simulation (LES). The models are characterised by a descriptionof anisotropy by use of explicit algebraic models for both the subgridscale(SGS) stress tensor (EASSM) and SGS scalar flux vector (EASSFM). LÄS MER

  3. 22. Development of a Multidimensional Residual Distribution Solver for Large Eddy Simulation of Industrial Turbulent Flows

    Författare :Doru Caraeni; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Thermal engineering; High-Order Compact Schemes.; Compressible Flows; Parallel Computations; Multidimensional Residual Distribution Schemes; Large Eddy Simulation; applied thermodynamics; Termisk teknik; termodynamik;

    Sammanfattning : This thesis presents the results of the author's research activity to develop a time-space accurate flow-solver for Large Eddy Simulations (LES), based on the Multidimensional Residual Distribution approach. The aim of this work is the attempt to develop a compact high-order algorithm which includes multidimensional flow physics, in hope of creating a better algorithm for LES of turbulent compressible flows. LÄS MER

  4. 23. Large Eddy Simulation of Turbulent Swirling Flows in Combustor Related Geometries

    Författare :Yajing Wu; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Swirling flow; swirler; vortex breakdown; precessing vortex core PVC ; large eddy simulation LES .;

    Sammanfattning : This thesis deals with the physics of turbulent swirling flows. Large eddy simulation (LES) method is used to investigate the vortex breakdown process, the precessing vortex core (PVC), and the effect of swirl number and flow field configuration on swirling flows. The study is based on an open source CFD code, \textit{OpenFoam}. LÄS MER

  5. 24. Large Eddy Simulation of Turbulent Combustion in PPC and Diesel Engines

    Författare :Rickard Solsjö; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; large eddy simulation LES ; turbulent spray combustion; Lagrangian particle tracking LPT ; diesel engines; partially premixed combustion PPC engines.;

    Sammanfattning : This thesis deals with large eddy simulations (LES) of turbulent combustion processes in direct injection internal combustion (IC) engines. Modeling of direct injection IC engine combustion involves modeling of turbulent spray/gas two-phase flow, modeling of chemical reactions of large hydrocarbon fuels and coupling of chemistry with turbulent flows. LÄS MER

  7. 25. 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