Bringing the Himalayas to Berlin

IAV's new climate roller dynamometer simulates altitudes of up to 5,300 meters

Reproducible results even under extreme conditions, fewer test drives in high mountainous regions and enhanced certainty in the development process: All this and more is provided by IAV's new altitude climate roller dynamometer. It is one of the world's most advanced and versatile systems of its kind and gives the company an important USP. IAV customers benefit from shorter development cycles and reduced costs for development and validation.

Globalization of the automotive markets is putting a new emphasis on altitude: While the highest mountain passes in Europe reach around 2,800 meters and about 3,700 meters in the USA, roads in South America climb to an impressive 4,700 meters. But the record is held in China and India, where cars need to operate reliably at altitudes of up to 5,300 meters. This has major implications for car manufacturers, who have to test new models un- der these extreme conditions during the development and validation cycle. But road tests in the Alps, Rocky Mountains, Andes or Himalayas are hugely complex and costly, as well as being dependent on the time of the year and unpredictable local weather conditions. There is therefore a demand for roller dynamometer testing that makes most of these road tests superfluous.

Pressure chamber in industrial monument

That is precisely what IAV's new altitude climate roller dynamometer does. The test facility is currently being installed by IAV in one of Berlin's oldest industrial monuments – the former ABOAG bus depot completed in 1926, which today is right next to IAV headquarters. The dynamometer is housed in a cuboid-shaped pressure chamber made of special reinforced concrete.

It is capable of simulating altitudes of up to 5,300 meters above sea level and generating temperatures between -30°C and 40°C, thus combining the conditions of "high and cold" (as in the Himalayas) and also "high and hot" (as on Mount Kilimanjaro). Maximum vehicle power of 450 kW and enough space even for small vans make it ideally equipped for nearly all test scenarios. It also permits repeated tests on recorded real-life drive profiles.

"Extreme altitude is a major challenge for every vehicle", explains Gerhard Buschmann, head of the Powertrain Mechatronics division at IAV. "They react like an untrained athlete who can't get enough air. Problems are encountered here particularly by vehicles with exhaust turbocharger and low cubic capacity. It is also possible that following a night of hard frost, cars won't start in the thin air next morning."

Such ambient conditions are easily simulated on the new climate roller dynamometer – all year round and under exactly reproducible boundary conditions. This leads to greater development certainty because engineers no longer have to wait for the next winter, for example, to test a new model in extremely cold temperatures and at high altitudes. Problems will be noticed at an earlier point in time and remedied faster, thus reducing development costs. The new RDE legislation also increases the demand for altitude climate roller dynamometers, stipulating test drives at altitudes of up to 1,300 meters, which are also possible on the new dynamometer.

Avoiding health risks for staff

Staff working for OEMs and development partners also benefit from the new dynamometer. Real road tests in high mountainous regions are physically strenuous, particularly when the drivers have to overcome great differences in altitude in a short period of time. "We don't have this problem with the altitude climate roller dynamometer, because we can leave the steering up to a robot when necessary", explains Buschmann. "We also reduce the burden on the environment by cutting out intercontinental transportation of vehicles and avoiding local test drives." Just another reason why the KfW (Kreditanstalt für Wiederaufbau – German promotional bank) is helping to fund the construction of the altitude climate roller dynamometer in the framework of its environmental protection program.

Needless to say that even the new dynamometer cannot replace all road tests because it is not so easy to simulate certain effects occurring in the real world, for example the impact of dust or the fluctuating quality of local fuel supplies. But IAV aims to make between 80 and 90% of all road tests superfluous in future.

At the moment, very few OEMs worldwide have a dynamometer of this standard, giving IAV a genuine USP among engineering partners. "This underlines our aspiration to realize turnkey projects and take on development work using our own infrastructure as far as possible", says Buschmann. Even if this means bringing the Himalayas to Berlin.