Sökning: "struts"

Visar resultat 6 - 10 av 17 avhandlingar innehållade ordet struts.

  1. 6. Aeroacoustic Prediction for Vertical Axis Wind Turbines

    Författare :Aya Aihara; Hans Bernhoff; Anders Goude; Mats Åbom; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fluid; acoustics; noise; sound; wind energy; vertical axis wind turbine; aerodynamics; airfoil; simulations; CFD; LES;

    Sammanfattning : This thesis investigates the aerodynamic and aeroacoustic prediction of vertical axis wind turbines, using computational fluid dynamics simulations. Noise pollution from wind turbines is one of the disadvantages of wind energy, calling for strategies to reduce noise levels. LÄS MER

  2. 7. Numerical and Experimental Investigations on Aerodynamic and Thermal Aspects of Rotating Wheels

    Författare :Alexey Vdovin; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; ventilation resistance; wind tunnel; brake cooling; ride height; aerodynamic moment; CFD; rim design; vehicle aerodynamics;

    Sammanfattning : With todays and future environmental legislations for CO2 and other emission gases, all vehicle manufacturers are forced to further develop tools and methods to make their vehicles more energy efficient and environmentally friendly. One option to achieve this is to reduce the aerodynamic resistance since it has a significant influence on the vehicle fuel consumption, especially for velocities higher than 50 km/h. LÄS MER

  3. 8. Vibrations and Dynamic Isotropy in Hexapods - Analytical Studies

    Författare :Behrouz Afzali Far; Mekanik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : The present work was initiated based on an industrial demand for designing a high-bandwidth hexapod of an advanced large optical telescope. In this dissertation, we have generalized this industrial problem to fully-parametric models of the hexapod vibrations as well as analytical studies on dynamic isotropy in parallel robots, which can be directly used in any hexapod application. LÄS MER

  4. 9. Aerothermal Investigation of an Intermediate Turbine Duct

    Författare :Carlos Arroyo; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; flowfield measurements; heat transfer measurements.; Intermediate turbine duct;

    Sammanfattning : Intermediate turbine ducts are used to guide the flow in turbofan engines from the short-radius high-pressure turbine to the large-radius low-pressure turbine. The demand for more efficient and silent jet engines and with a reduced environmental impact requires turbofans with increasingly higher by-pass ratios. LÄS MER

  5. 10. Micro-structural based acoustic modelling of anisotropic open cell materials

    Författare :Eva Lundberg; Huina Mao; Bradley Semeniuk; Peter Göransson; Mathieu Gaborit; Romain Rumpler; Peter Göransson; Elke Deckers; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sound absorption; vehicle; anisotropic; foam; micro-structure; resource efficient; transfer matrix method; ljudabsorption; anisotrop; skum; mikrostruktur; TMM; fordon; resurseffektiv; Farkostteknik; Vehicle and Maritime Engineering;

    Sammanfattning : A method for the calculation of the acoustic performance of open-cell foammaterials is discussed. From a known micro-structural geometry and theconstituent material, the relevant acoustic properties are computed using apreviously published analytical method for the calculation of the dynamicdrag impedance and a previously published method for the calculation of theelastic moduli. LÄS MER