In a modern linehaul cab-over commercial vehicle, the type long associated with European manufacturing, around one third of the available mechanical energy is needed to overcome the air resistance and according to Daimler Trucks & Bus, the new Actros in which a MirrorCam replaces the customary rear-view mirrors contributes, up to 1.5 per cent to overall fuel savings.
Initial estimates suggest this results in up to five per cent less fuel consumption than its predecessor.
Improved aerodynamics achieved here through computer modelling and extensive wind tunnel testing with design modifications such as new concave cab side deflectors on the cab all significant factors in the crucial goal of lowering fuel consumption.
At Untertürkheim, Germany, the wind tunnel enables the developers to generate wind speeds of up to 250 kilometres per hour.
"Here, in parallel to computer-based flow calculations – i.e. digital simulations using computational fluid dynamics (CFD) – random spot checks were carried out to confirm the aerodynamic improvement of conceptual components," says Michael Hilgers, Head of CAE Vehicle Functions in Commercial Vehicle Development at Mercedes-Benz.
The aerodynamic measurements are then validated during on-road testing.
Over the last decade and more recently the fuel consumption of the Actros has been steadily reduced.
"In typical long-distance transport operations, for example, savings of up to 15 percent have been achieved between 2011 and the introduction of the new Actros from 2019," said Daimler Truck & Bus in a statement.
Further fuel economy has been confirmed by the new Actros in inner-city traffic by as much as five per cent.
Daimler said optimised Predictive Powertrain Control (PPC) cruise control and transmission control systems, in addition to new rear axle ratios and the recent aerodynamic improvements to the truck's cab have all been influential in the latest findings in diminishing resistance and fuel consumption reductions.