Objectives and content
The growing traffic density, particularly in suburban and city centres, leads to the inhabitants being increasingly subjected to and disturbed by traffic noise.
The proposed activities aim to provide a contribution in solving the environmental problem of the urban and suburban traffic noise pollution, with an optimisation of the tyres and road surfaces.
The main problem is to obtain an effective global traffic noise reduction. The current method for evaluation of noise levels is IS0 362 on IS0 asphalt 10844. However it can be observed that no European road asphalt is really equivalent to IS0 10844 (ref. Sandberg - "Tire road noise - A subject of international concern"). Also, human noise level perception can be quite different when compared to the measurements and results ,, obtained using microphones, as used in all the noise approval methods. Clearly the human ear is not a microphone and therefore its response curve is not linear in the frequency domain, and is selective in noise identification. Furthermore, test procedures are limited because the human ear is not always 7.5m from the noise source and contributions of single noise sources (engine, exhaust system, tyres, etc.) are directional. From these limitations, the research will address the problem of (running vehicles) real noise reduction in general European real road conditions.
The focus of the research is:
- How to measure and evaluate the tyre conditions to noise pollution in actual European road conditions. From these measurements a ranking of noise, can be made, so that improved products or surfaces can be identified.
- How to optimize both the tyre product and the road surface. (This will include modelling and simulation techniques).
This will result in new products and surfaces capable of reducing noise pollution. It will be reasonable to obtain 1 - 2 dB(A) tyre noise reduction on the same surface; 3 - 5 dB(A) noise reduction due to road surface. Such result will dramatically drop the emitted energy due to the intensity of tyre/road noise pollution (by up to 50%).
The results of the research will be prototypes of new tyres (including "all season" and "winter"), new road surfaces, new measurement and evaluation techniques for road noise pollution, guidelines on how to plan future "low noise" European road surfaces, traffic condition.
The summary of the project is to improve the environment by reducing the traffic noise pollution. This is turn will improve driving safety as drivers will be subjected to reduced vehicle internal noise fatigue.
Funding SchemeCSC - Cost-sharing contracts
92252 La Garenne-colombes
CV10 0TU Nuneaton