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The vehicles will experience the simulated conditions at the UK’s first dedicated Real Driving Emissions (RDE) testing centre, opened today by automotive supplier and development partner Mahle.
The company invested £8m in the “one-of-a-kind” facility, spurred on by the 2017 introduction of the Worldwide Harmonised Light Vehicle Test Procedure (WLTP). The new standard ensures manufacturers test emissions based on the simulation of real-world driving conditions, replacing the slower, shorter and less stringent New European Driving Cycle tests. WLTPs include more time at higher speeds and loads, plus inefficient aggressive acceleration and braking.
Testing chamber equipment includes a four-wheel-drive chassis dynamometer from Horiba and an altitude and climatic control system from Weiss, letting Mahle engineers simulate a wide range of environments and weather conditions, from -40ºC to 60ºC.
“It’s the only chamber in the UK and one of only three independent facilities in Europe which has full altitude capabilities, so we can create altitude conditions of 0-5,000m,” said Simon Williams, head of RDE testing, to Professional Engineering.
“For example, on one day we can simulate the roads of southern Spain in summer, and the next do Andorra in the mountains in winter, when it’s really cold. So we can offer our customers all the flexibility.”
With no capabilities for water to stream down on to the car, the chamber might sometimes be less forbidding than the surrounding East Midlands roads. Operators can simulate loads and drag, however, replicating the effect of weather on a car’s performance. “All of these aspects can be controlled in the facility – without getting your car wet,” said Williams.
The centre’s opening follows several years of the most intense scrutiny that emissions testing has ever seen. Politicians and members of the public became more aware of the damaging effects of nitrogen oxides, particulates and other emissions on people’s health after Volkswagen installed illegal “defeat devices” in cars to limit emissions below real-world levels during laboratory testing.
“We can make sure that concerns like that are reduced,” said Mahle spokesman Daren Mottershead. “There is an element of control that wasn’t there before.”
That control includes replicating the climate conditions, climbs and descents of real-world testing routes in the chamber. After collecting data from route testing, said Williams, “we can go and cross-correlate that to the chamber and we have got a very good guarantee that we’re within a very small percentage of error”.
He added: “The front wheels are turning, the car can ‘feel’ like it is moving down the road.”
Manufacturers will frequently use the centre during development, allowing engineers to make adjustments before plans go to the production line. Results will help optimise engine calibrations and ensure they are ready for a wide range of environmental conditions, as required by the WLTP and the EU’s upcoming RDE package four.
The strict new rules will force manufacturers to be “much, much more robust against any potential RDE conditions you can think of,” said Williams. “That’s where we are trying to come in.”
Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.