Vehicle noise emission legislation - Opportunity for innovative exhaust system solutions

摘要

With the introduction of UNECE Regulation 51 Revision 3, concerns from environmentalists as well as from the automotive industry have been raised. In general, the legislative requirements, which last until 2020, on vehicle noise emission became less demanding compared to the previously enforced requirements, considering only the mandatory part of the vehicle type approval test. However, looking at the upcoming stages aiming to reduce the permissible vehicle noise limits, an actual reduction of the noise emitted by motor vehicles is expected. Moreover, relevant legislation introduced Additional Sound Emission Provisions (ASEP) on the linearity of the vehicle noise emission beyond the vehicle operation points evaluated during the vehicle type approval test. Innovative exhaust system solutions such as the application of active sound generation systems or acoustic valves have been assessed in terms of compliance with the relevant legislation. In summary, the legislative requirements and its future amendments in permissible noise emission limits lead to an increased challenge for exhaust system components to comply with relevant legislation. However, the application of smart exhaust system solutions involving active sound generation systems and acoustic valves helps to achieve sporty vehicle sound while being compliant with relevant legislation.