Cutting out in-car noise

Licensing opportunity

Scientists at the Fraunhofer Institute for Industrial Mathematics ITWM in Kaiserslautern, Germany, have developed an interior car roof lining that is better at absorbing noise inside a car, and unlike existing linings is made of a single type of material, and thus easily recycled.

“Our simulation programme enabled us to perform numerous virtual experiments to determine whether our recyclable PET fabric would be suitable as a noise absorber,” says ITWM project manager Volker Schulz. “Previous solutions involved the time-consuming, cost-intensive task of building prototypes to test the materials. Simulation allowed us to reduce this stage to a minimum number of tests.”

The simulation programme, called Geo-Dict, makes it possible to vary various parameters, such as the orientation and diameter of the fibres, or the degree to which the material is compressed, and then run the programme to see if the virtual structure has the desired acoustic properties. “We can keep on modifying the microstructure of the absorber until we arrive at the optimum noise-damping result, without ever having to build a single prototype,” Schulz explains.

Geo-Dict can be applied to any situation where noise impinges on comfort. It provides a low-cost means of perfecting the design of many materials, including floor carpets and wall coverings.