Sökning: "train noise"
Visar resultat 1 - 5 av 50 avhandlingar innehållade orden train noise.
1. Noise from Train Cooling Fans
Sammanfattning : This thesis concerns a study undertaken on a railway vehicle cooling fan system. Several design modifications were proposed and tested in the laboratory in order to evaluate different noise control measures. The most effective noise control measure involving combining lots of different measures gave 7 dB(A) noise reduction. LÄS MER
2. Characterization of train-induced aerodynamic loads on high-speed railway vertical noise barriers
Sammanfattning : High-Speed Railway (HSR) technology requires the deployment of noise barriers to mitigate noise pollution affecting nearby residents. As train speeds increase, so does the magnitude of aerodynamic effects such as aerodynamic noise and the pressure on these barriers, meaning that these structures require robust sound insulation and structural load-bearing capacities. LÄS MER
3. INDOOR NOISE FROM URBAN RAILBOUND TRANSPORT
Sammanfattning : Methods for determination of indoor noise and vibrations from urban rail bound transport are presented in this work. Both measurement methods and empirical prediction methods are described. The data and results are taken from field measurements of noise and vibrations from the trams and metro trains of Oslo. LÄS MER
4. Vertical Axis Wind Turbines : Tower Dynamics and Noise
Sammanfattning : Vertical axis wind turbines (VAWTs) have with time been outrivaled by the today common and economically feasible horizontal axis wind turbines (HAWTs). However, VAWTs have several advantages such as the possibility to put the drive train at ground level, lower noise emissions and better scaling behavior which still make them interesting for research. LÄS MER
5. On the Directivity of Railway Noise Sources
Sammanfattning : This dissertation deals with the directivity of railway noise. The directivity of railway noise is of particular importance when we have high-rise buildings close to the track, tunnel openings, partial barriers, or when we calculate the maximum sound pressure level during a pass-by based on the sound power level of the different sub-sources of a train. LÄS MER