Sökning: "low-level jet"

Visar resultat 1 - 5 av 8 uppsatser innehållade orden low-level jet.

  1. 1. Turbulence Intensity During Low-Level Jets in the Baltic Sea

    Kandidat-uppsats, Uppsala universitet/Luft-, vatten- och landskapslära

    Författare :Thomasson August; [2021]
    Nyckelord :Low-Level Jet; Turbulence intensity; Shear sheltering; LiDAR; Baltic Sea; Low-Level Jet; Turbulensintesitet; Shear sheltering; LiDAR; Östersjön;

    Sammanfattning : Low-level jets (LLJs) are local wind speed maximums in the atmospheric boundary layer. In the Baltic Sea, LLJs are frequently occurring in spring and summer. It is an important phenomena to consider for wind energy parks, and changes in turbulence during the jets can effect the efficiency of said parks. LÄS MER

  3. 2. Characterisation of Low-Level Jets and their Influence on Low-Level Clouds over the Baltic Sea; Östergarnsholm Observatory, Sweden

    Kandidat-uppsats, Lunds universitet/Fysiska institutionen; Lunds universitet/Förbränningsfysik

    Författare :Johan Lundberg; [2021]
    Nyckelord :Low-level jets; Low-level clouds; LLJs; LLCs; Boundary layer; ABL; CBH; Lidar; Ceilometer; Turbulent intensity; Physics and Astronomy;

    Sammanfattning : In this study, about two years of data from Östergarnsholm in the Baltic Sea are used to analyse offshore low-level clouds (LLCs) influenced by low-level jets (LLJs) in the marine atmospheric boundary layer. The LLJs are passages of strong horizontal winds near the surface and are measured using a Doppler LiDAR, which provides information about the wind speed and wind direction up to 300 meters. LÄS MER

  4. 3. Nocturnal jets in Skåne: an analysis of data from Hyltemossa research tower

    Kandidat-uppsats, Lunds universitet/Fysiska institutionen; Lunds universitet/Förbränningsfysik

    Författare :Tove Fast; [2019]
    Nyckelord :Physics and Astronomy;

    Sammanfattning : A nocturnal jet is a low level air jet that is often seen at an altitude below 500 m during night time conditions. It can reach wind speeds of storm force and is thus of importance for aviation and also for transport of e.g. moisture and pollutants in the lower troposphere. LÄS MER

  5. 4. Assessment of noise prediction methods over water for long range sound propagation of wind turbines

    Magister-uppsats, Uppsala universitet/Institutionen för geovetenskaper

    Författare :Lukas Mylonas; [2014]
    Nyckelord :Wind energy; Sound; Noise; Offshore; Helmholtz; Partial Differential Equation; Low-Level Jet;

    Sammanfattning : Wind turbine noise is a re-emerging issue in the wind industry. As the competition for sites with good wind potential on land is rising, offshore projects in coastal areas seem as a reasonable alternative to onshore. LÄS MER

  7. 5. Analysis of three ventilation systems in an office: Mixing, displacement and confluent jet ventilation system. : Analysis of temperature gradient, tracer gas and thermal comfort.

    Magister-uppsats, Avdelningen för bygg- energi- och miljöteknik

    Författare :Julio J. Peña Malo; Igor Panjkov Zafra-Polo; [2013]
    Nyckelord :Ventilation systems; mixing; displacement; confluent; confluent jet; thermal comfort; temperature gradient; tracer gas;

    Sammanfattning : Scandinavian countries have always been the first in investigation and development of new ventilation systems. In the last years, engineers from Finland and Sweden are studying a new ventilation system known “Confluent jet ventilation system” which is trying to improve displacement and mixing results. LÄS MER