Increasingly stringent legal noise limits for vehicles and the rapidly advancing electrification of mobility are raising the demands on the acoustic performance of underbody systems.

With the use of chamber resonators, Autoneum’s new lightweight Ultra-Silent Tune technology significantly reduces external tyre rolling noise while ensuring a quiet and comfortable driving experience inside the vehicle.

The technology’s sound-absorbing performance is achieved by acoustic chambers of different shapes and sizes, created by applying an embossed polyester foil to the side of the Ultra-Silent underbody shield facing away from the noise source. These capture the sound waves emitted by the car tyres, modulate them according to their respective geometry and reflect them back onto the porous carrier material.

Compared to conventional single-layer underbody shields, whose acoustic performance is mainly determined by the noise-reducing properties of the product side facing the tyres, Ultra-Silent Tune exploits both sides of the component, which significantly improves acoustic absorption. As a result, exterior tyre rolling noise is reduced by between 0.5-1 dBA.

In addition to a high proportion of recycled PET fibres, the underbody shields can be manufactured from 100% polyester, enabling them to be fully recycled at the end of vehicle life.

The thickness of the multilayer construction can also be flexibly adapted to the packaging spaces of different vehicle models.

Ultra-Silent Tune underbody shields are already in pre-development at various vehicle manufacturers in Europe.

www.autoneum.com