Sökning: "Railway rolling noise"

Visar resultat 1 - 5 av 16 avhandlingar innehållade orden Railway rolling noise.

1. 1. On the Directivity of Railway Noise Sources

   Författare :Xuetao Zhang; Chalmers tekniska högskola; []
   Nyckelord :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;

   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

3. 2. Tread Braking of Railway Wheels - Noise-related Tread Roughness and Dimensioning Wheel Temperatures

   Författare :Tore V Vernersson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rail chill; block material; temperature; heat partitioning; railway; corrugation; thermoelastic analysis; tread braking; noise;

   Sammanfattning : Block braking is a commonly used braking system for freight wagons and other types of railway vehicles. One or several brake blocks are pressed against the tread (running surface) of the wheel, which is also in rolling contact with the rail. LÄS MER

4. 3. Applicable directivity description of railway noise sources

   Författare :Xuetao Zhang; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; directivity; the Doppler factor; scattered fluid sound; railway noise; perpendicular dipole pair;

   Sammanfattning : For a sound source, directivity is an important parameter to specify. This parameter also reflects the physical feature of the sound generation mechanism. For example, turbulence sound is of quadrupole directivity whilst fluid-structure interaction often induces a sound of dipole characteristic. LÄS MER

5. 4. Modelling the acoustic performance of slab tracks

   Författare :Jannik Theyssen; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; numerical modelling; railway noise; rolling noise; slab track; acoustic optimisation;

   Sammanfattning : Transport is a major contributor to anthropogenic greenhouse gas emissions. Railway transport has a small footprint compared to other means of transport. This is one reason for the construction of new high-speed railway lines world-wide. LÄS MER

7. 5. Development of new techniques for the numerical modelling of railway track dynamics. Application to rolling noise assessment

   Författare :Blas Blanco; Leif Kari; Ernesto García-Vadillo; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Track modelling; Timoshenko element; local deformation; distributed supports; moving Green s functions; rolling noise;

   Sammanfattning : The numerical modelling is widely employed for the prediction of the railway track dynamic behaviour, which is of utmost importance for the characterisation of the undesired medium-high frequency phenomena, such as corrugation, wheel-out-of-roundness and noise emission. This study is devoted to the improvement of railway track numerical modelling, the efficient resolution of the problem in the time domain and the assessment of rolling noise for different approaches of the track modelling. LÄS MER