Author(s): Pieren Reto, Lauper Demian, Heutschi Kurt
Characteristics of railway noise depend on the type of rolling stock, track parameters and the operating conditions. Auralization in combination with visualization is a relatively new technology to support decision-making and to enable the inclusion of human perception in the assessment of different noise scenarios. Within this virtual environment, mitigation actions or potential design alternatives can be demonstrated in an intuitive way. This makes it an essential modern technique to communicate between stakeholders and to non-experts. The auralization of a vehicle pass-by event is based on separate modules: sound generation, propagation and reproduction. This allows for an investigation of mitigation measures at the source as well as on the propagation paths. The rail vehicle as an acoustical source is modeled by a series of moving point sources that represent physical sources. These sources emit specific signals that are artificially generated using parametric sound synthesis. For rolling and impact noise, emissions are generated for each axle using a physically-based synthesis model that uses rail and wheel roughness data as input. The audio signals at the virtual observer point are rendered via a loudspeaker array or headphones, whereas the visualizations are presented with a screen or a head-mounted display. With this approach, relevant railway noise mitigation measures such as changes of rail and wheel roughness, avoidance of wheel flats, variants of aggregates, and the effects of a barrier or a cutting can be demonstrated and compared.
Name: Mr Reto Pieren