Search for dissertations about: "stall"

Showing result 1 - 5 of 24 swedish dissertations containing the word stall.

  1. 1. Vertical Axis Wind Turbines Electrical System and Experimental Results

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Jon Kjellin; Uppsala universitet.; [2012]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; VAWT; H-rotor; start-up; all-electric control; Power Coefficient; stall; tip speed ratio; Renewable energy; Measurement systems; PM-generator;

    Abstract : The wind power research at the division of Electricity at Uppsala University is aimed towards increased understanding of vertical axis wind turbines. The considered type of wind turbine is an H-rotor with a directly driven synchronous generator operating at variable speed. READ MORE

  2. 2. Aerodynamics of Vertical Axis Wind Turbines Development of Simulation Tools and Experiments

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Eduard Dyachuk; Uppsala universitet.; [2015]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wind power; vertical axis turbine; H-rotor; simulations; streamtube model; vortex model; dynamic stall; measurements; blade; force; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Abstract : This thesis combines measurements with the development of simulation tools for vertical axis wind turbines (VAWT). Numerical models of aerodynamic blade forces are developed and validated against experiments. The studies were made on VAWTs which were operated at open sites. READ MORE

  3. 3. Flow instabilities in centrifugal compressors at low mass flow rate

    University dissertation from Kungliga Tekniska högskolan : Kungliga Tekniska högskolan

    Author : Elias Sundström; KTH.; KTH.; [2017]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Centrifugal compressor; flow instabilities; rotational flows; rotating stall; surge; compressible Large Eddy Simulation; Teknisk mekanik; Engineering Mechanics;

    Abstract : A centrifugal compressor is a mechanical machine with purpose to convert kineticenergy from a rotating impeller wheel into the fluid medium by compressingit. One application involves supplying boost air pressure to downsized internalcombustion engines (ICE). READ MORE

  4. 4. Numerical investigation of blade flutter at or near stall in axial turbomachines

    University dissertation from Stockholm : Energiteknik

    Author : Wolfgang Höhn; KTH.; [2000]
    Keywords : ;

    Abstract : During the design of the compressor and turbine stages oftoday's aeroengines aerodynamically induced vibrations becomeincreasingly important since higher blade load and betterefficiency are desired. Aerodynamically induced vibrations inturbomachines can be classified into two general categories,i.e. READ MORE

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

    University dissertation from Uppsala : Acta Universitatis Upsaliensis

    Author : Victor Mendoza; Uppsala universitet.; [2018]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 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