Search for dissertations about: "acd"

Showing result 1 - 5 of 23 swedish dissertations containing the word acd.

  1. 1. Numerical Computations of Wakes Behind Wind Farms : A tool to study Farm to Farm interaction

    Author : Ola Eriksson; Stefan Ivanell; Anna Rutgersson; Simon-Philippe Breton; Philippe Chatelain; Uppsala universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; Wind turbine; Wind power; Wind farm; Wakes; Long distance wakes; Farm-Farm; Farm to farm interaction; Wind farm cluster; Large Eddy simulations; LES; Actuator disc method; ACD; CFD; Ellipsys3D; Prescribed boundary layer; PBL; Forced boundary layer; FBL; Meteorologi; Meteorology;

    Abstract : More and larger wind farms are planned offshore. As the most suitable sites to build are limited these new wind farms will be constructed near to each other in so called wind farm clusters. Behind the wind turbines in these farms there is a disrupted flow of air called a wake that is characterized by reduced wind speed and increased turbulence. READ MORE

  2. 2. Numerical Computations of Wakes Behind Wind Farms

    Author : Ola Eriksson; Stefan Ivanell; Simon-Philippe Breton; Anna Rutgersson; Dan Henningson; Niels Troldborg; Uppsala universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Wind turbine; Wind power; Wind farm; Wakes; Long distance wakes; Farm-Farm; Farm to farm interaction; Wind farm cluster; Large Eddy simulations; LES; Actuator disc method; ACD; CFD; Ellipsys3D;

    Abstract : More and larger wind farms are planned offshore. As the most suitable build sites are limited wind farms will be constructed near to each other in so called wind farm clusters. Behind the wind turbines in these farms there is a disrupted flow of air called a wake that is characterized by reduced wind speed and increased turbulence. READ MORE

  3. 3. Stock data, trade durations, and limit order book information

    Author : Ola Simonsen; Kurt Brännäs; Johan Knif; Umeå universitet; []
    Keywords : SOCIAL SCIENCES; SAMHÄLLSVETENSKAP; SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Finance; Maximum likelihood; Estimation; ACD; News; Multivariate; Intraday; Market; Economics; Nationalekonomi;

    Abstract : This thesis comprises four papers concerning trade durations and limit order book information. Paper [1], [2] and [4] study trader durations, e.g., the time between stock transactions in intra-day data. READ MORE

  4. 4. Wind power wake modelling : Development and application of an actuator disc method for industrial utilization

    Author : Nikolaos Simisiroglou; Stefan Ivanell; Thorsten Lutz; Uppsala universitet; []
    Keywords : NATURAL SCIENCES; NATURVETENSKAP; Wind power; Offshore wind farm; Wakes; Actuator Disc Method ACD ; Computational Fluid Dynamics CFD ; Reynolds Average Navier–Stokes RANS ; WindSim; PHOENICS;

    Abstract : As a wind turbine extracts energy from the wind it creates a region downstream where the wind velocity is decreased and the urbulence intensity is increased, this region is commonly called the wake region. Today’s wind farms include a large number of wind turbines position in tight layouts. READ MORE

  5. 5. A body force method for high precision offshore wake modelling simulations

    Author : Nikolaos Simisiroglou; Uppsala universitet; []
    Keywords : ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wind power; Offshore wind farm; Wakes; Actuator disc method ACD ; Computational fluid dynamics CFD ; Reynolds Average Navier-Stokes RANS ; WindSim; PHOENICS;

    Abstract : .... READ MORE