Sökning: "airfoil"

Visar resultat 1 - 5 av 31 avhandlingar innehållade ordet airfoil.

  1. 1. Large Eddy Simulation of the Flow around a High-Lift Airfoil

    Författare :Simon Dahlström; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; mildly separation; hybrid RANS LES; incompressible finite volume; airfoil; transition; large Eddy simulation; approximate wall boundary condition;

    Sammanfattning : The work presented in this thesis concerns the efforts of conducting a Large Eddy Simulation (LES) around an airfoil. The airfoil is close to stall, near maximum lift and the Reynolds number is high. In the flow a transitional separation bubble is present. LÄS MER

  3. 2. Computational studies of passive vortex generators for flow control

    Författare :Florian von Stillfried; Arne Johansson; Stefan Wallin; Sinisa Krajnovic; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; passive flow control; vortex generator; statistical modelling; turbulence; separation prevention; flat plate; diffuser; high-lift design; airfoil; Fluid mechanics; Strömningsmekanik;

    Sammanfattning : Many flow cases in fluid dynamics face undesirable flow separation due torising static pressure on wall boundaries. This occurs e.g. due to geometry as ina highly curved turbine inlet duct or e. LÄS MER

  4. 3. Aeroacoustic Prediction for Vertical Axis Wind Turbines

    Författare :Aya Aihara; Hans Bernhoff; Anders Goude; Mats Åbom; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluid; acoustics; noise; sound; wind energy; vertical axis wind turbine; aerodynamics; airfoil; simulations; CFD; LES;

    Sammanfattning : This thesis investigates the aerodynamic and aeroacoustic prediction of vertical axis wind turbines, using computational fluid dynamics simulations. Noise pollution from wind turbines is one of the disadvantages of wind energy, calling for strategies to reduce noise levels. LÄS MER

  5. 4. Prediction of Wing Section Lift and Drag from Numerical Solutions of the Navier-Stokes Equations

    Författare :Björn Regnström; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; airfoil; incompresible flow; computational fluid dynamics; transition; numerical analysis; boundary layer stability;

    Sammanfattning : A Navier-Stokes finite difference method is developed and applied to two-dimensional, incompressible, viscous flow around wing sections at medium to high Reynolds numbers. An important feature of such flows is laminar boundary layers with spatially amplified Tollmien-Schlichting waves initiating transition to turbulence. LÄS MER

  7. 5. Aerodynamic and Aeroacoustic Analysis of a Multi-Element Airfoil using Hybrid RANS/LES Modeling Approaches

    Författare :Bastian Nebenführ; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ffowcs-Williams and Hawkings; HYB0; noise; hybrid RANS LES; multi-element airfoil; CAA; Kirchhoff; Curle; high-lift;

    Sammanfattning : Global hybrid RANS/LES simulations were used for computing the turbulent flow around a three-element airfoil. Based on the results of the flow computations, a comprehensive analysis of the flow properties was performed. LÄS MER