Traffic Noise Propagating from Vibration of Railway Wagon

Abstract

Traffic noise has become a serious environmental hazard as more cars are purchased and driven. To help objectively and subjectively reduce perceived noise load, methods to analyze traffic noise offer an important means of creating a design to reduce noise output from main sources and transmission routes. Acoustic analysis using BEASY and dynamic analysis using ANSYS are conducted to forecast noise at a distance of 15 m from a railway wagon travelling at 100 km/h. This noise is based on structural vibration only and it excludes other noise sources from the railway wagon. The simulation results demonstrate that the overall noise at 15 m from a railway wagon car is 85.1 dB(L) from linear energy weighting calculation and 72.9 dB(A) from the A-weighting calculation. In this study, noise level propagating from vibration of the railway wagon is measured or calculated using A-weighting filter to simulate the frequency response of the human ear. The study results can be useful to factories, companies, or organizations and can provide an important resource and help reduce traffic noise. This can be achieved by predetermining the test location and structure configuration and adapting local planning and thus preventing excessive traffic noise in residential areas.

Analytic Formulation for the Sound Absorption of a Panel Absorber under the Effects of Microperforation, Air Pumping, Linear Vibration and Nonlinear Vibration

“…Note that this case does not consider any perforation effect and other effects. There are two peaks in each of the two figures, which are due to the (1,1) and (1,3) mode resonances, respectively. It can be seen that the peaks due to the (1,1) mode resonance are more nonlinear.…”

“…Numerous studies of structural-acoustic interaction have been carried out in recent decades (e.g., [1][2][3][4][5][6]). Particularly, the topics of microperforated panel and panel absorber have attracted the interest of many researchers.…”

Nonlinear Dynamic Analysis of Railway Wagon End Wall under the Action of Granular Media

“…Substituting (19) and (20) into (17) and equating the coefficients of 0 and 1 on both sides, we can obtain…”

“…The key issues to consider are the nonlinear constitutive relation of the granular media, the simulation of contact relationship between granular media and end wall, and the simulation of the boundary condition to set up the finite element model of the end wall. We define the height ratio of the granular media = / , by introducing the theory of finite element modeling of the retaining wall structure; we considered the special contact relationship (e.g., see [14][15][16][17][18][19][20][21][22]) between granular media and continuum and set up finite element models with different ; the FEM model is shown in Figure 8. Deformation of granular media relates to current stress state and loading process because granular media are anisotropic material and do not follow Hook's law.…”