The Significance of Tire Noise
A newly published study in Recent Patents on Mechanical Engineering has found that belt structure can have a significant impact on the overall vibration noise associated with a given tire’s functionality. The research effort, titled “Study of the Influence of Tire Belt Structure on Vibration Noise,” sought to determine whether this aspect of tire design could be easily manipulated to affect total sound produced. A team of researchers from China’s Jiangsu University’s School of Automotive and Traffic Engineering completed the project late last year. The group launched its research because of the increasing relevance of tire noise in the overall equation of vehicle noise, vibration and harshness (NVH). As other components of NVH like air resistance and engine noise are reduced by innovation, the sound produced by tires looms as a larger piece of the puzzle.
The Role of Belt Structure
The researchers tested a variety of belt structures for volume differences, controlling for speed, surface material and tire type. For tire aficionados, their test tire was the Chinese-produced TBR 295/80R22.5. Using the modal acoustic transfer vector technique in conjunction with acoustic boundary element simulation analysis, the team tested various belt designs for the level of noise they produced. What they found could have major implications for the future of vehicular sound management.
Essentially, the study indicated that optimization of the belt structure reduced vibration noise by more than 7.5 decibels in comparison to the factory version of the tire. Consider that otolaryngologists typically reference 85 decibels as the level of sound that is safe for human ears. That gap between the optimized tire belt structure and the default represents roughly 9 percent of that threshold. If we were able to cut down the sound produced by vehicles by 7.5 decibels overall, the chances that any given exposure would qualify as damaging would be dramatically reduced. Clearly, this aspect of tire design is one that deserves more attention going forward.
The Future of Tire Design
That type of sweeping reform in tire manufacturing won’t happen overnight. More studies are required to determine how best to reproduce optimized belt structure in tires of different sizes and types. What this project shows, however, is that further research could bring worthwhile advances to the industry. The continual increase in the total number of cars on the road demands that we find ways to keep NVH in check. Optimal tire belt structure across a variety of vehicle types can play a major role in that.