Sökning: "streamline curvature"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden streamline curvature.

  1. 1. Development and analysis of turbulence models for flows with strong curvature and rotation

    Författare :Olof Grundestam; KTH; []
    Nyckelord :Turbulence model; nonlinear modelling; streamline curvature; high-lift aerodynamics;

    Sammanfattning : An explicit algebraic Reynolds stress model (EARSM) based ona pressure strain rate model including terms tensoriallynonlinear in the mean velocity gradients is developed in orderto improve predictions for .ows with strong curvature and/orrotation. LÄS MER

  3. 2. Modelling and simulation of turbulence subject to system rotation

    Författare :Olof Grundestam; Arne Johansson; Sharath Girimaji; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct numerical simulations; least-squares method; turbulence model; nonlinear modelling; system rotation; streamline curvature; high-lift aerodynamics; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : Simulation and modelling of turbulent flows under influence of streamline curvature and system rotation have been considered. Direct numerical simulations have been performed for fully developed rotating turbulent channel flow using a pseudo-spectral code. The rotation numbers considered are larger than unity. LÄS MER

  4. 3. Receptivity of Boundary-Layer Flows over Flat and Curved Walls

    Författare :Lars-Uve Schrader; Luca Brandt; Dan Stefan Henningson; Gregoire Casalis; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Boundary-layer receptivity; laminar-turbulent transition; swept-plate boundary layer; Görtler flow; leading-edge effects; swept-wing flow; crossflow vortices; Görtler rolls; disturbance streaks; wall roughness; free-stream turbulence; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : Direct numerical simulations of the receptivity and instability of boundary layers on flat and curved surfaces are herein reported. Various flow models are considered with the aim to capture aspects of flows over straight and swept wings such as wall curvature, pressure variations, leading-edge effects, streamline curvature and crossflow. LÄS MER

  5. 4. Numerical modeling of Swirling Flows in Gas Turbine Burners

    Författare :Robert-Zoltán Szász; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : The present thesis focuses on the numerical simulation of the flowfield in gas turbine burners. Due to the higher and higher requirements regarding pollutant emissions there is a need for new combustion technologies. In gas turbines one method to obtain low pollutant levels is the use of lean premixed or partially premixed combustion. LÄS MER

  7. 5. Numerical Modeling of Flows Related to Gas Turbine Combustors

    Författare :Robert-Zoltán Szász; Strömningsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; plasma; fluid dynamics; plasmas; Gaser; fluiddynamik; Gases; vortex breakdown; swirl; CFD; gas turbine;

    Sammanfattning : The thesis focuses on the numerical simulation of the flow field in gas turbine burners. Due to tougher and tougher requirements on low levels of emission of pollutants there is a need for new combustion technologies. In gas turbines one method to attain low pollutant levels is the use of lean premixed combustion. LÄS MER