Search for dissertations about: "atmospheric acoustics"

Showing result 1 - 5 of 26 swedish dissertations containing the words atmospheric acoustics.

  2. 1. Turbulence modelling applied to the atmospheric boundary layer

    Author : Werner Lazeroms; Arne Johansson; Geert Brethouwer; Evgeni Fedorovich; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; turbulence; RANS models; explicit algebraic Reynolds-stress models; buoyancy; stable stratification; thermal convection; atmospheric boundary layer;

    Abstract : Turbulent flows affected by buoyancy lie at the basis of many applications, both within engineering and the atmospheric sciences. A prominent example of such an application is the atmospheric boundary layer, the lowest layer of the atmosphere, in which many physical processes are heavily influenced by both stably stratified and convective turbulent transport. READ MORE

  4. 2. Aeroacoustic Prediction for Vertical Axis Wind Turbines

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

    Abstract : 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. READ MORE

  5. 3. Wind Turbine Sound in Cold Climates

    Author : Kristina Conrady; Anna Rutgersson; Karl Bolin; Sabine von Hünerbein; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; atmospheric acoustics; wind turbine sound; outdoor sound propagation; cold climates; Meteorology; Meteorologi;

    Abstract : The increase in the number of wind turbines (WTs) in populated areas in cold climates increases the number of people potentially being affected by WT sound. Outdoor sound propagation is strongly dependent on meteorological conditions, however, limitations in the knowledge exist regarding the implications of meteorological conditions in cold climates. READ MORE

  6. 4. Laser spectroscopic analysis of atmospheric gases in scattering media

    Author : Mikael Sjöholm; Atomfysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fjärranalys; Remote sensing; Laser spectroscop; Scattering of light; Diode lasers; acoustics; optics; Electromagnetism; optik; akustik; Elektromagnetism; Optical absorption; Nondestructive testing: optical; Interdisciplinary applications of physics; Laser technology; Atom- och molekylärfysik; Atomic and molecular physics; LIDAR remote sensing; Laserteknik;

    Abstract : Laser spectroscopic techniques for gas analysis under various influences of light scattering are explored in a wide spectral range from the ultraviolet to the infrared. The techniques rely on spectrally narrow-band light sources that are used in differential optical absorption measurements. READ MORE

  7. 5. Turbulence-resolving simulations for engineering applications

    Author : Bastian Nebenführ; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LES; Aeroacoustics; Forest canopy; Airframe noise; hybrid RANS LES; Turbulence-resolving simulation; Wind-turbine fatigue loads; Wind power;

    Abstract : Most fluid flows of industrial interest are turbulent and their accurate representation may be of vital importance for the design process of new products. To date, steady RANS methods are usually employed for the simulation of turbulent flows of everyday engineering problems. READ MORE