Sökning: "aircraft noise"

Visar resultat 21 - 25 av 60 avhandlingar innehållade orden aircraft noise.

  1. 21. Numerical Simulations of Noise Reduction Devices for Aero Engines

    Författare :Haukur Hafsteinsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustic liner; G3D; CAA; CFD; CD-nozzle; LES;

    Sammanfattning : Increasing air traffic and denser population around airports have led to stricterregulations on aircraft noise. The engine is the main source of noise of jet aircraft.Decreasing jet engine noise can in some cases reduce sonic fatigue andthereby increase the engine lifetime. LÄS MER

  3. 22. Optimization of Aircraft Arrival Operations for Improved Environmental Efficiency

    Författare :Henrik Hardell; Tatiana Polishchuk; Valentin Polishchuk; Ramon Dalmau-Codina; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : The transportation sector, accounting for about one fifth of all greenhouse gas emissions, is facing a significant transformation in order to become more climate-friendly. In terms of air transportation, there are several important steps on the way to making flying sustainable both for the planet itself and for people directly or indirectly being exposed to its effects. LÄS MER

  4. 23. Cardiovascular and metabolic effects of long-term traffic noise exposure

    Författare :Charlotta Eriksson; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :;

    Sammanfattning : Traffic noise is an increasingly common environmental exposure affecting large parts of the European population. Since the auditory system is directly linked to the sympathetic nervous and the endocrine systems, noise may induce a stress response, influencing several physiological, metabolic and immunological processes. LÄS MER

  5. 24. Turbomachinery Aeroacoustic Calculations using Nonlinear Methods

    Författare :Martin Olausson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nonlinear; CFD; Time Spectral; CAA; Ffowcs-Williams Hawkings; Broadband; Time lag; Computational Aeroacoustics; Fan-Noise; Rotor-Stator interaction; Buffer layer; Oscillating sphere; Newton-GMRES; Computational Fluid Dynamics; Acoustic analogies; Sponge; Counter-Rotating Propfan; Harmonic Balance Technique; Tone; FWH; Chorochronic periodicity; Hybrid RANS LES;

    Sammanfattning : Noise regulations for aircraft that fly over populated areas are becoming continuously stricter. This in combination with increasing computational capabilities has boosted interest in aeroacoustic computations in the aerospace industry. LÄS MER

  7. 25. Numerical Methods for Aeroacoustic Analysis of Turbomachinery

    Författare :Daniel Lindblad; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Convective Ffowcs Williams - Hawkings Equation; Computational Aeroacoustics; Acoustic Analogy; Von Neumann Stability Analysis; Tonal Noise; CAA; Harmonic Balance Method; Counter Rotating Open Rotor;

    Sammanfattning : Air transportation is today an integral part of many peoples life and it continuously grow to serve more of us in new and ingenious ways. There are however negative sides to this growth as well, such as increased noise around airports and more CO2 emissions, which must be addressed if aviation is to be part of a sustainable future. LÄS MER