Sökning: "passive scalar"

Visar resultat 1 - 5 av 18 avhandlingar innehållade orden passive scalar.

  1. 1. Experimental study of passive scalar mixing in swirling jet flows

    Författare :Ramis Örlü; Henrik Alfredsson; Peter Johansson; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fluid mechanics; swirling jet; turbulence; passive scalar; mixing; hot-wire anemometry; cold-wire; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : Despite its importance in various industrial applications there is still a lack of experimental studies on the dynamic and thermal field of swirling jets in the near-field region. The present study is an attempt to close this lack and provide new insights on the effect of rotation on the turbulent mixing of a passive scalar, on turbulence (joint) statistics as well as the turbulence structure. LÄS MER

  3. 2. 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

  4. 3. Turbulence measurements in fiber suspension flows : experimental methods and results

    Författare :Monika Carina Fällman; Fritz Bark; Daniel Söderberg; Fredrik Lundell; Thomas Wikström; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluid; flow; turbulent; turbulence; paper; pulp; fiber; fibre; suspension; two-phase; experimental; conductivity; micro-probes; passive scalar; ultrasonic; Doppler shift; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : Turbulent mixing is present in many pulp and paper processes. It is a particularly important factor in the design and improvements of the paper machine headbox, influencing the final paper structure. LÄS MER

  5. 4. 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

  7. 5. Direct and Large-Eddy Simulations of Turbulent  Boundary Layers with Heat Transfer

    Författare :Qiang Li; Philipp Schlatter; Dan S Henningson; Gary Coleman; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; direct numerical simulation DNS ; large-eddy simulation LES ; turbulent boundary layer; passive scalar; coherent structures; free-stream t urbulence FST ; structure ensemble dynamics SED ; massively parallel simulations;

    Sammanfattning : .... LÄS MER