Sökning: "Wall-Bounded Turbulent Flows"

Visar resultat 6 - 10 av 32 avhandlingar innehållade orden Wall-Bounded Turbulent Flows.

  1. 6. Streak breakdown and transition control in wall-bounded flows

    Författare :Fredrik Lundell; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fluid mechanics; active control; laminar-turbulent transition; freestream turbulence; Engineering mechanics; Teknisk mekanik; TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : .... LÄS MER

  3. 7. Experimental study on turbulent boundary-layer flows with wall transpiration

    Författare :Marco Ferro; Jens Fransson; Bengt Fallenius; Joseph Klewicki; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulent boundary layer; boundary-layer suction; boundary-layer blowing; wall-bounded turbulent flows; self-sustained turbulence; Engineering Mechanics; Teknisk mekanik;

    Sammanfattning : Wall transpiration, in the form of wall-normal suction or blowing through a permeable wall, is a relatively simple and effective technique to control the behaviour of a boundary layer. For its potential applications for laminar-turbulent transition and separation delay (suction) or for turbulent drag reduction and thermal protection (blowing), wall transpiration has over the past decades been the topic of a significant amount of studies. LÄS MER

  4. 8. Flow facility design and experimental studies of wall-bounded turbulent shear-flows

    Författare :Björn Lindgren; KTH; []
    Nyckelord :fluid mechanics; wind.tunnels; asymmetric diffuser; turbulent boundary layer; flow structures;

    Sammanfattning : The presen present thesis spans a range of topics within thearea of turbulent flows, ranging from design of flow facilitiesto evaluation aluation of scaling laws and turbulence modelingdeling aspects through use of experimental data. A newwind-tunnel has been designed, constructed and evaluated at theDept. of Mechanics, KTH. LÄS MER

  5. 9. Stability analysis and transition prediction of wall-bounded flows

    Författare :Ori Levin; KTH; []
    Nyckelord :Boundary layer; wall jet; algebraic growth; exponential growth; lift-up effect; streamwise streaks; Tollmien-Schlichting waves; free-stream turbulence; roughness element; transition prediction; Parabolized Stability Equations; Direct Numerical S;

    Sammanfattning : Disturbances introduced in wall-bounded .ows can grow andlead to transition from laminar to turbulent .ow. In order toreduce losses or enhance mixing in energy systems, afundamental understanding of the . LÄS MER

  7. 10. Experiments on oblique transition in wall bounded shear flows

    Författare :Per Elofsson; KTH; []
    Nyckelord :;

    Sammanfattning : This thesis considers laminar-turbulent transition in wall bounded shear flows, with a focus on transition emanating from a pair of oblique disturbance waves. The oblique waves interact nonlinearly and transfers disturbance energy into streamwise vortices, which generate streamwise streaks through a linear mechanism that operates also at conditions where stability theory predicts decay of all eigenmodes. LÄS MER