Search for dissertations about: "gränsskikt"

Showing result 16 - 20 of 30 swedish dissertations containing the word gränsskikt.

  2. 16. Experimental study on turbulent boundary-layer flows with wall transpiration

    Author : Marco Ferro; Jens Fransson; Bengt Fallenius; Joseph Klewicki; KTH; []
    Keywords : 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;

    Abstract : 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. READ MORE

  4. 17. Boundary Conditions for Spectral Simulations of Atmospheric Boundary Layers

    Author : Erik Boström; Philipp Schlatter; Bernard J. Geurts; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : An atmospheric boundary layer (ABL) is generally a very high Reynolds number boundary layer over a fully rough surface that is influenced by different external forces. Numerical simulations of ABLs are typically demanding, particularly due to the high Reynolds numbers. READ MORE

  5. 18. Strategies for Molecular Engineering of Macroscopic Adhesion and Integrity Focusing on Cellulose Based Materials

    Author : Andrea Träger; Lars Wågberg; Eva Malmström; Anna Carlmark; Matthew Tirrell; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; blockcopolymer; cellulose; adhesion; ATRP; micelle; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Abstract : Many aspects of modern human life pose a strain on the delicate ecosystems around us. One example is marine litter – mainly various plastic items – which accumulate in the marine environment, where they cause problems for the fauna, such as ingestion and entanglement. READ MORE

  6. 19. Adaptive and model-based control in laminar boundary-layer flows

    Author : Nicolò Fabbiane; Dan S. Henningson; Aimee S. Morgans; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Flow control; Control theory; Optimal control; Adaptive control; Boundary-layer flow; Fluid dynamics; Plasma actuator; Surface hot-wire; Transition delay;

    Abstract : In boundary-layer flows it is possible to reduce the friction drag by breaking the path from laminar to turbulent state. In low turbulence environments, the laminar-to-turbulent transition is dominated by local flow instabilities – Tollmien-Schlichting (TS) waves – that exponentially grows while being con- vected by the flow and, eventually, lead to transition. READ MORE

  7. 20. Time, space and control: deep-learning applications to turbulent flows

    Author : Luca Guastoni; Ricardo Vinuesa; Hossein Azizpour; Philipp Schlatter; Andrea Beck; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulence; deep learning; deep reinforcement learning; flow control; turbulens; djupinlärning; djupförstärkningsinlärning; flödeskontroll; Teknisk mekanik; Engineering Mechanics;

    Abstract : In the present thesis, the application of deep learning and deep reinforcement learning to turbulent-flow simulations is investigated. Deep-learning models are trained to perform temporal and spatial predictions, while deep reinforcement learning is applied to a flow-control problem, namely the reduction of drag in an open channel flow. READ MORE