New technique will make quiet tyres to reduce noise pollution from motorways

The technique, developed by a team from Purdue University in the United States, creates a mathematical ‘fingerprint’ identifying which features produce the most noise when the tyre tread comes into contact with the road surface. Vibrations in the tread blocks and the underlying reinforcing belts radiate energy outward, producing sound much like the vibrating cones in stereo speakers, with different portions of the tyre vibrating at different speeds, the fastest making the most noise.

“Most of the environmental noise nuisance from interstate highways is tyre noise,” said Stuart Bolton, a professor of mechanical engineering at Purdue University. “If you are anywhere near an interstate [highway], much of the noise that you hear is generated by the tyre-road interaction, with the exception of some noise from heavy trucks.”

The vibrations from the various parts of the treadband of the tyres, including the reinforcing, are displayed on a graph, but in order to be more accurate, the entire tyre needs to be modelled in a three-dimensional cross section, says Bolton. “We are working to make the model much more tyre-like,” he said.

“We created this numerical model that we can pretend is a tyre, giving it the properties of a tyre and running a ‘test’ in the computer as if we were doing a real experiment,” said Bolton. “This illustrates that fact that you can predict the vibration and noise differences related to various design features. It’s a new approach to looking at tyre vibration.”

The results of the Purdue team’s work will be presented on 27 August at the 30th International Congress and Exhibition on Noise Control Engineering in The Hague. The study was sponsored by the US Department of Transportation, Ford Motor Co, and a number of tyre manufacturers.