New test bench for measuring rolling resistance
Tires play a central role in certain automotive mega trends. They can also make a noticeable contribution to reducing fuel consumption. Reason enough for IAV to open a new tire rolling resistance test bench with a wide range of testing possibilities for OEMs and tire manufacturers.
They are easily underestimated due to the inconspicuous way they do their job in the vehicle: the tires. But this does them an injustice. After all, tires are growing increasingly important, with their key role in some of the current mega trends. Electric vehicles with their limited battery capacity need tires with particularly low rolling resistance to help increase their range. In autonomous vehicles, comfort aspects will become even more important, thus making new demands of the tires. In the context of vehicle connectivity, tires need sensors that measure air pressure and wear and send the values to a control center. “In future, vehicles will depend more than ever on high-performance, low-wear tires with low rolling resistance”, summarizes Simon Heine, Senior Vice President for Chassis at IAV.
And there are more requirements besides. In conventional vehicles they are expected to help reduce fuel consumption. A good tire can save up to three percent compared to a poor tire. This is important for OEMs as well as car owners. Tires with low rolling resistance can help them to comply with the CO2 fleet limits. Since 2012, the EU tire label with its efficiency classes A to G shows how well a certain model performs. What is more, the WLTP is based on real driving conditions so that the tire’s rolling resistance is included in the type approval. “The examples show that tires will play an even more important role in automotive engineering in future”, says Heine
Test bench for tire classes C1, C2 and C3
OEMs and tire manufacturers need modern test benches for developing and assessing tires. Since February, IAV offers a state-of-theart test facility in Gifhorn. “Our test bench measures energy loss in the freely rolling wheel,” Heine explains. “Tire deformation causes some of the losses and must thus be seen in conflict with the grip that tires should have at the end of the development process.” The new test bench permits detailed examination of the tires. Possibilities here include basic research with a focus on reduced CO2 emissions and extending the range of electric vehicles, or ascertaining the potential for reducing fleet consumption rates, or rolling resistance measurements as per ISO 28580, or monitoring the quality of standard tires, as well as tire labeling as per EC 1222/2009 (rolling resistance, wet grip performance and passby noise impact).
“We can test small car tires as well as large tires for heavy-duty trucks”, says Heine. “With a maximum speed of 270 km/h, we even fulfill the requirements for super sports cars.” Validation in the reference lab of Continental Reifen Deutschland GmbH means that the measurement results are internationally accepted. “We can also react flexibly to customer requests, and test even large numbers of tires at short notice”, says Heine.
- Drum diameter: 2 m
- Maximum speed: 270 km/h, accuracy: ± 0.05 km/h
- Maximum wheel load: 63 kN, accuracy: ± 0.02 %
- Upgraded for tire classes C1, C2 and C3
- Noise level: approx. 80 dB
- Static camber adjustment up to ± 6 °
- Fulfils all requirements of ISO 28580
- References: Goodyear/Dunlop (D), RDW (NL), Apollo Vredestein (NL), TARRC (GB)