Search for dissertations about: "BYPASS TRANSITION"

Showing result 1 - 5 of 17 swedish dissertations containing the words BYPASS TRANSITION.

  2. 1. Transition in Particle-laden Flows

    Author : Joy Klinkenberg; Luca Brandt; Shuisheng He; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Transition; modal analysis; non-modal analysis; multi-phase flow; particle-laden; heavy particles; light particles;

    Abstract : This thesis presents the study of laminar to turbulent transition of particle laden flows. When a flow becomes turbulent, the drag increases one order of magnitude compared to a laminar flow, therefore, much research is devoted to understand and influence the transition. READ MORE

  4. 2. Edge states and transition to turbulence in boundary layers

    Author : Taras Khapko; Dan Henningson; Philipp Schlatter; Yohann Duguet; Rich Kerswell; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; boundary layer; transition to turbulence; direct numerical simulation; edge state; free-stream turbulence; bypass transition; probabilistic cellular automaton; turbulence at the onset; laminar–turbulent coexistence; laminarisation; Engineering Mechanics; Teknisk mekanik;

    Abstract : The focus of this thesis is the numerical study of subcritical transition to turbulence in boundary-layer flows. For the most part, boundary layers with uniform suction are considered. Constant homogeneous suction counteracts the spatial growth of the boundary layer, rendering the flow parallel. READ MORE

  5. 3. Experimental studies of bypass transition and its control

    Author : Fredrik Lundell; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluid mechanics; active control; Laminar-turbulent transition; free-stream turbulence; Engineering mechanics; Teknisk mekanik;

    Abstract : Bypass transition, i.e. transition of a boundary layer at subcritical Reynolds numbers, has been studied. Fundamental studies of the phenomenon as such have been performed side by side with experiments aimed at controlling, i. READ MORE

  6. 4. 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

  7. 5. Optimisation and control of shear flows

    Author : Antonios Monokrousos; Dan S. Henningson; Laurette Tuckerman; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; shear flows; flow control; optimal disturbances; Lagrange method; transition to turbulence; non-linear dynamics; Engineering mechanics; Teknisk mekanik;

    Abstract : Transition to turbulence and flow control are studied by means of numerical simulations for different simple shear flows. Linear and non-linear optimisation methods using the Lagrange multiplier technique are employed. READ MORE