Sökning: "turbulence age"

Visar resultat 1 - 5 av 11 avhandlingar innehållade orden turbulence age.

  1. 1. The age of transported scalars in fluid mechanics

    Författare :Federico Ghirelli; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; grate furnace; velocity correlation; fluid age; scalar age; turbulence model; residence time; energy spectrum; turbulence age;

    Sammanfattning : Computational fluid dynamics (CFD) is applied to the reacting flow in the freeboard of a 30MW biofuel fired grate furnace and results are validated by comparison with data from an extensive measurement campaign. The influence of the fuel bed model on the results of the freeboard model is investigated. LÄS MER

  2. 2. Noninvasive characterization of patients with monomorphic ventricular tachycardia and ventricular fibrillation using the signal-averaged electrocardiogram. A study on late potentials and spectral turbulence in patients with ischemic heart disease and in healthy subjects

    Författare :Christer Gottfridsson; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; signal-averaged ECG; ventricular tachycardia; ventricular fibrillation; late potentials; spectral turbulence; bundle branch block;

    Sammanfattning : Many people die suddenly from sustained ventricular tachyarrhythmias caused by ischemic heart disease, and the sudden death may be the first presentation of heart disease. If the patients at risk of ventricular tachyarrhythmia could be identified, some patients may be saved. LÄS MER

  3. 3. Fluxes and Mixing Processes in the Marine Atmospheric Boundary Layer

    Författare :Erik Olof Nilsson; Anna Rutgersson; Harm Jonker; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Waves; Growing sea; Swell; Marine boundary layer; Air-sea interaction; Mixing; Momentum flux; Wind stress; Flux attenuation; Sensor separation; Large eddy simulation; Multiresolution analysis; Coupling; Wave model; Climate model; Wave age; Meteorology; Meteorologi;

    Sammanfattning : Atmospheric models are strongly dependent on the turbulent exchange of momentum, sensible heat and moisture (latent heat) at the surface. Oceans cover about 70% of the Earth’s surface and understanding the processes that control air-sea exchange is of great importance in order to predict weather and climate. LÄS MER

  4. 4. Wind-wave interaction effects on offshore wind energy

    Författare :Ali Al Sam; Strömningsteknik; []
    Nyckelord :wind-wave; swell; atmospheric boundary layer; marine atmospheric boundary layer; atmospheric turbulence; Large-eddy simulation; actuator line; wind sea; offshore technology; wind energy; wind turbine; aerodynamic;

    Sammanfattning : This thesis is devoted to the investigation of the impacts of fast moving ocean surface waves on the aerodynamics of offshore wind turbines. The impacts of non-locally generated waves (swell) on the Marine Atmospheric BoundaryLayer (MABL) and thereby on offshore wind turbine aerodynamics are studied numerically by using Large Eddy Simulations and the Actuator Line Method. LÄS MER

  5. 5. Atmosphere-ocean Interactions in Swell Dominated Wave Fields

    Författare :Alvaro Semedo; Anna Rutgersson; Oyvind Saetra; Piero Lionello; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Waves; Wind sea; Swell; Swell propagation; MABL; Air-sea interaction; Momentum flux; Wave climate; Coupling; Wave age; Empirical Orthogonal functions; Wave model; Climate model; WAM; RCA; wave heights; Meteorology; Meteorologi; Meteorologi; Meteorology;

    Sammanfattning : Ocean wind waves represent the atmosphere-ocean boundary, playing a central role in the air-sea exchanging processes. Heat, mass and momentum are transferred across this boundary, with waves mediating the exchange of principally the momentum between the winds and the ocean surface. During the generation process waves are called wind sea. LÄS MER