Conference_programme: 25.2 - Tyre / road noise
Lecture: The noise reduction potential of “silent tyres” on common road surfaces
Author(s): Hammer Emanuel, Bühlmann Erik
Summary:
Since tyre/road noise dominates at velocities above 15 km/h for modern cars, the acoustic optimisation of both road surface and tyre may be an effective means of reducing road traffic noise. With its tyre label, the European Commission is attempting to encourage the purchase of low-noise tyres by benchmarking their noise emission together with measurements on fuel consumption and wet grip. Several studies have sug-gested, however, that the noise reduction stated on the label cannot be directly transferred to real world environments because label values refer to the noise levels obtained on a special standard surface which is usually not found on roads. As a basis for decision-makers, this study, evaluates the noise reduction poten-tial of “silent tyres” on the most common road surfaces in Switzerland and elsewhere in Europe. Noise emissions were measured for 14 carefully selected tyres with different dimensions, profiles and noise la-bels on a set of 12 road surfaces of varying type. The measurements were conducted using a modified CPX (close-proximity) trailer allowing for adjustments to the tyre load in order to respect the UN/ECE 117 standard’s requirements regarding carrying capacity. The study revealed that the narrowest tyre of the sample (a common tyre for e.g. electric BMW i3) is about 5 dB quieter than the widest assessed tyre (a common tyre for e.g. Audi RS5). Within the same dimension class the noise reduction potential was found to be up to 4 dB. The obtained noise reductions are similarly high over all assessed road surfaces. Since other studies have indicated that a tyre’s noise reduction potential does not significantly diminished with tyre age, it is recommended for policy makers to devote more resources to the proliferation of “silent tyres” (e.g. by improving label relevance and understanding) since this may contribute towards lower traffic noise levels on a large scale.
Corresponding author
Name: Dr Emanuel Hammer
e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
Country: Switzerland
