Search for dissertations about: "train noise"

Showing result 1 - 5 of 50 swedish dissertations containing the words train noise.

2. 1. Noise from Train Cooling Fans

   Author : Yan Jiang; Mats Åbom; Thomas Carolus; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Acoustics; Akustik;

   Abstract : 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. READ MORE

4. 2. Characterization of train-induced aerodynamic loads on high-speed railway vertical noise barriers

   Author : Dongyun Liu; Gabriel Sas; Chao Wang; Jaime Gonzalez; Lennart Elfgren; Yongming Tu; Paolo Zampieri; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Aerodynamic pressure; Computational fluid dynamics; Train geometry; High-speed railway; High-speed train; Load calculation model; Vertical noise barrier; Byggkonstruktion; Structural Engineering;

   Abstract : 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. READ MORE

5. 3. INDOOR NOISE FROM URBAN RAILBOUND TRANSPORT

   Author : SIGMUND OLAFSEN; Teknisk akustik; []
   Keywords : Tramway noise; acoustics; Indoor noise;

   Abstract : 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. READ MORE

6. 4. Vertical Axis Wind Turbines : Tower Dynamics and Noise

   Author : Erik Möllerström; Jonny Hylander; Fredric Ottermo; Göran Sidén; Hans Bernhoff; Mats Åbom; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; VAWT; H-rotor; eigenfrequency; semi-guy-wired tower; noise emission; sound power level;

   Abstract : 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. READ MORE

7. 5. On the Directivity of Railway Noise Sources

   Author : Xuetao Zhang; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; railway traction noise; railway rolling noise; line source; railway aerodynamic noise; moving source; equivalent source line; De-Dopplerization; sound emission time; sound immission time; directivity; the Doppler factor;

   Abstract : 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. READ MORE