Sökning: "Geert Brethouwer"

Hittade 4 avhandlingar innehållade orden Geert Brethouwer.

  1. 1. Numerical studies of turbulent wall-jets for mixing and combustion applications

    Författare :Daniel Ahlman; Arne Johansson; Geert Brethouwer; Micheal Manhart; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : Direct numerical simulation is used to study turbulent plane wall-jets. The investigation is aimed at studying dynamics, mixing and reactions in wall bounded flows. The produced mixing statistics can be used to evaluate and develop models for mixing and combustion. LÄS MER

  3. 2. 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

  4. 3. Turbulent flows over permissive boundaries and porous walls

    Författare :Seyed Morteza Habibi Khorasani; Shervin Bagheri; Geert Brethouwer; Alfredo Soldati; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct numerical simulations; wall-bounded turbulence; flow control; porous walls; heat transfer; Direkta numeriska simuleringar; väggbunden turbulens; flödeskontroll; porösa väggar; värmeöverföring; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : This thesis investigates how in wall-bounded turbulent flows changes to the wall can induce changes in the flow. To this end, we investigate the use of wall boundary conditions meant to mimic the effect of textured surfaces. LÄS MER

  5. 4. Turbulence modelling applied to the atmospheric boundary layer

    Författare :Werner Lazeroms; Arne Johansson; Geert Brethouwer; Evgeni Fedorovich; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; turbulence; RANS models; explicit algebraic Reynolds-stress models; buoyancy; stable stratification; thermal convection; atmospheric boundary layer;

    Sammanfattning : Turbulent flows affected by buoyancy lie at the basis of many applications, both within engineering and the atmospheric sciences. A prominent example of such an application is the atmospheric boundary layer, the lowest layer of the atmosphere, in which many physical processes are heavily influenced by both stably stratified and convective turbulent transport. LÄS MER