An innovative tire test center is nearing completion in France. Mastermind Arnaud Dufournier gives an insight into its creation and what it will offer
In October 2014, Tire Technology International reported on the plans for a new tire labeling and R&D test facility south of Clermont-Ferrand, France. Just over a year later, following frustrating delays with the planning authorization, the European Tire Test Center (E2TC), an indoor facility in Auzat-la-Combelle, is at last close to welcoming its first customers.
E2TC will be opened in phases. The buildings at 10,000m2, large enough to cover any expansion for the next few years were finished by the beginning of September. Newly installed and first in line for commercial use is a rolling resistance measurement machine, the first of as many as 12 if demand dictates, which will be calibrated and aligned with the virtual reference machine in collaboration with UTAC in early December. The first customer tests are scheduled for January 2016 shortly before E2TC’s creator, the well-known tire test and analysis specialist, Dufournier Technologies, will be exhibiting at Tire Technology Expo in Hanover. Next on the schedule is the first of four wet-grip test tracks for tire label measurements, which could be running in April. Toward the end of 2016, when the innovative, carriage-and-rail tracks for wet-grip testing are well established, attention will turn to a longer, faster rail track for dry-grip studies and other R&D applications.
The driving force behind E2TC is confident that demand for its services will be high. “For rolling resistance, it seems that there is high and permanent demand for this type of test, probably because the tests take a long time,” says Arnaud Dufournier, president and CEO of the company that bears his name.
“For the wet-grip measurement, the interest is quite different it’s in the technology. People are looking at R&D applications, not just label tests. We have had discussions with all the biggest tire manufacturers, who are very interested in the principle of the testing and the technology we are using to do it. The idea is to use this principle not only for wet grip, but also for some dry measurements; and not only for braking, but also to measure transverse force and for other applications.”
Dufournier points to three reasons for the high interest in this new, indoor approach to wet-grip label testing: temperature control, elimination of wind and test repeatability.
“Managing wind and temperature changes everything,” he stresses. “Knowing as we do the impact of temperature on tire performance, managing temperature is key to improving test results and understanding what you do. When you are working on wet grip, even just a little wind can mean you have more water on one side of the track than the other, giving you a completely different result. And if you move your tire 20cm to the right or left on the test track, then you will change the result [due to inconsistency in the surface], hurting your repeatability. But with our system, you know precisely where you will do the measurement. I think the combination of managing the environment and knowing exactly where we will start the braking maneuver will lead to a level of performance reliability that nobody else can reach on a track today.”
It should be noted that Continental’s AIBA facility already offers a repeatable, climate-controlled indoor environment for wet braking tests, but it remains an in-house, non-commercially available test center and does not share E2TC’s ambitious scale. “In addition,” says Dufournier, “E2TC is focused on tire measurement only and needs no cars, which introduce a dispersion in tire force and positions and bring additional delay and cost to tire measurements.”
At the time of writing, the first parts for E2TC’s bespoke carriage-and-rail test systems had already been produced and were awaiting assembly. Earlier this year, Dufournier’s engineers built a scale model to prove the principle of the technology and check the parts. Assuming the system works as intended, he knows that the remaining item to be managed is the track surface itself, which will need careful monitoring to ensure that precious test repeatability.
“Track wear is a problem on every test track, because people always brake in more or less the same area,” Dufournier assesses. “Our approach is to treat the surface as a consumable item. We will use ASTM or SRTT reference tires to regularly measure the part of the track we’re using, and then move the test when the results are no longer right. When we’ve run every possible line, we will resurface it every year, every six months, or even every three months, as required. The system has been designed so that it’s very easy to change the pavement.”
Each wet-grip test section measures 4 x 75m and will accommodate two test rails and carriages. Not only can the carriage be braked in different places along the rail to ensure a constant surface, but each rail can also be moved laterally within a usable test width of about 1.5m, to take full advantage of the available asphalt strip.
The plan is to run the first wet-grip track for around three months to make sure it’s operating as planned before installation of the second one begins, rising to four in all. In parallel, work will start on the dedicated R&D track in the neighboring building. This will be dedicated to tire modeling, analysis and other R&D studies such as footprint 3D force distribution. Space is available to extend it from the current 100m length to 160m at a later date.
That’s not to say that testing in the wet-grip or rolling-resistance laboratories will be dedicated solely to EU label-rating testing. By adding sensors to its rolling-resistance test bench as well as to its wet-grip test machine, E2TC plans to capture data to understand why a particular label result has been achieved, not just what it is. Dufournier expects this to build into a successful labeling-improvement consultancy business.
“We are in discussions with many customers about this type of service,” he reveals. “The new [wet-grip] measurement system’s stability and repeatability, and its capability to manage everything from the camber to the braking force, the way you apply the braking, the load and the water level all of that is very important for understanding why the tire is at its level, and how we can improve it to the next level. We will work with the customer to improve the construction, materials, tread pattern, manufacturing everything. We’ll then take a new labeling measurement and repeat the cycle if we still have not reached the target.”
Above: Aerial view of E2TC. Key:
1. Tire storage and logistics
2. Four wet-grip test tracks
3. 1-12 rolling resistance benches
4. Building for future high-speed and R&D test track
November 26, 2015