Search for dissertations about: "Actuator Line"

Showing result 1 - 5 of 28 swedish dissertations containing the words Actuator Line.

  2. 1. Wind-turbine wakes - Effects of yaw, shear and turbine interaction

    Author : Elektra Kleusberg; Dan Henningson; Philipp Schlatter; Stefan Ivanell; Johan Meyers; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wind-turbine wakes; yaw; tip-vortex breakdown; shear; computational fluid dynamics; actuator-line method; spectral-element method; Vindturbinsvakar; girning; turbulent nedbrott hos spetsvirvlar; skjuvning; vakinteraktion; beräkningsströmningsdynamik; actuator line-metod; spektralelementmetod; Engineering Mechanics; Teknisk mekanik;

    Abstract : The actuator-line method is used together with the incompressible Navier–Stokes equations to investigate the flow development behind wind turbines. Initial investigations focus on providing a thorough validation of the implementation in the spectral-element flow solver Nek5000 against existing numerical and experimental datasets. READ MORE

  4. 2. Aerodynamic Studies of Vertical Axis Wind Turbines using the Actuator Line Model

    Author : Victor Mendoza; Anders Goude; Hans Bernhoff; Robert Flemming Mikkelsen; Uppsala universitet; []
    Keywords : wind power; vertical axis wind turbines VAWTs ; actuator line model ALM ; dynamic stall model DSM ; atmospheric boundary layer ABL ; wake deflection; atmospheric boundary layer ABL ; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Abstract : This thesis addresses the unsteady aerodynamics involved in the operation of vertical axis wind turbines (VAWTs). The main focus is to represent and understand the most relevant phenomena within the resulting flow pattern as the wake structure, loads on the different turbine components and the performance of the rotor. READ MORE

  5. 3. Wafer-level heterogeneous integration of MEMS actuators

    Author : Stefan Braun; Göran Stemme; Martin A. Schmidt; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Microelectromechanical systems; MEMS; silicon; wafer-level; integration; heterogeneous integration; transfer integration; packaging; assembly; wafer bonding; adhesive bonding; eutectic bonding; release etching; electrochemical etching; microvalves; microactuator; Shape Memory Alloy; SMA; NITINOL; TiNi; NiTi; cold-state reset; bias spring; stress layers; crossbar switch; routing; switch; switch array; electrostatic actuator; S-shaped actuator; zipper actuator; addressing; transfer stamping; blue tape; Computer engineering; Datorteknik;

    Abstract : This thesis presents methods for the wafer-level integration of shape memory alloy (SMA) and electrostatic actuators to functionalize MEMS devices. The integration methods are based on heterogeneous integration, which is the integration of different materials and technologies. READ MORE

  6. 4. Numerical computations of wind turbine wakes and wake interaction : Optimization and control

    Author : Karl Nilsson; Dan Henningson; Stefan Ivanell; Martin O. L. Hansen; KTH; []
    Keywords : Actuator disc method; Actuator line method; Blade element momentum method; Wind turbine wake; Wake interaction; CFD; LES; EllipSys3D;

    Abstract : In the present thesis the wake flow behind wind turbines is analyzed numerically using large-eddy simulations. The wind turbine rotors are modeled by using either the actuator disc method or the actuator line method in which the blades are represented by body forces computed with airfoil data. READ MORE

  7. 5. Numerical computations of wind turbine wakes

    Author : Stefan S. A. Ivanell; Dan Henningson; Peinke Joachim; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Actuator Line Model; Actuator Disc Model; Wind Turbine Wake; CFD; LES; EllipSys3D; Fluid mechanics; Strömningsmekanik;

    Abstract : Numerical simulations of the Navier-Stokes equations are performed to achieve a better understanding of the behaviour of wakes generated by wind turbines. The simulations are performed by combining the in-house developed computer code EllipSys3D with the actuator line and disc methodologies. READ MORE