Search for dissertations about: "sinuous instability"

Found 3 swedish dissertations containing the words sinuous instability.

  2. 1. Effects of free-stream turbulence and three-dimensional roughness on boundary layer transition

    Author : Santhosh Babu Mamidala; Jens H. M. Fransson; Bengt E. G. Fallenius; Jonathan Morrison; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; boundary-layer transition; intermittency; free-stream turbulence; electret microphones; isolated roughness; sinuous instability; varicose instability; Engineering Mechanics; Teknisk mekanik;

    Abstract : External disturbances such as free-stream turbulence (FST), and isolated three-dimensional roughness are strong disturbance sources to the laminar boundary layers (BLs), which can lead to a rapid transition to turbulence. The transition process eventuates to increase in skin-friction coefficient and heat transfer rate and hence, both of the aforementioned disturbance sources have practical importance. READ MORE

  4. 2. Study of generation, growth and breakdown of streamwise streaks in a Blasius boundary layer

    Author : Luca Brandt; KTH; []
    Keywords : Fluid mechanics; laminar-turbulent transition; boundary layer flow; transient growth; streamwise streaks; lift-up effect; receptivity; free-stream turbulence; streak instability; secondary instability; Direct Numerical Simulation.;

    Abstract : Transition from laminar to turbulent flow has beentraditionally studied in terms of exponentially growingeigensolutions to the linearized disturbance equations.However, experimental findings show that transition may occuralso for parameters combinations such that these eigensolutionsare damped. READ MORE

  5. 3. Numerical studies of bypass transition in the Blasius boundary layer

    Author : Luca Brandt; KTH; []
    Keywords : Fluid Mechanics; laminar-turbulent transition; boundary layer flow; transient growth; streamwise streaks; secondary instability;

    Abstract : Experimental findings show that transition from laminar toturbulent ow may occur also if the exponentially growingperturbations, eigensolutions to the linearised disturbanceequations, are damped. An alternative non-modal growthmechanism has been recently identi fied, also based on thelinear approximation. READ MORE