We have featured the Mercedes-Benz Actros in a previous design feature. That Actros spent 2600 hours in the wind tunnel to turn out with fluid, seamless surfaces that ensured nearly a 12 to 15 percent lesser wind resistance compared to its predecessor.
Now Mercedes-Benz takes it to the next level, with the designers coming up with the Aero Trailer which has 18 percent lesser wind resistance.
A number of changes work together to drastically lower the wind resistance of the entire trailer. A front airdam on the trailer reduces the distance to the tractor unit and lowers the wind resistance by one percent. The side trim panels which you will notice from the pictures, are slightly drawn-in at the front and have an opening at the rear. This steers the air in the direction of the parallelogram shaped rear diffuser. The side panels contribute an eight-percent improvement. The diffuser links up with the underbody panelling. This improves the wind resistance by one to two percent.
A rear end taper measuring slightly more than 400 mm in length forms a crucial part of the aerodynamic concept. Mercedes-Benz says it features folding elements to facilitate access to the load compartment. The rear end taper improves wind resistance by a further seven percent.
This 18 percent lower wind resistance contributes to a reduction in fuel consumption amounting to almost five percent in real-life road traffic, says Mercedes Benz. In the case of an average mileage of 150,000 km a year this means a saving of some 2000 l of diesel fuel and savings of over five tonnes of CO2 per annum.
There’s a catch though. The aero trailer’s only restriction is the fact that its length measurement exceeds the currently permissible limit in Europe by almost half a metre, due to the tail-end extension. Mercedes Benz says, the handling and manoeuvrability are not in any way compromised by the taper. It is here that changes to legislation are necessary. Good luck with that Mercedes Benz! It isn’t as sad as it sounds, exceptions have already been made as in the case of tail lifts and transportable fork-lift trucks.
The aero trailer is the flagship of the new “Truck and Trailer 7plus” initiative being launched by Mercedes-Benz. By taking a holistic approach to the tractor unit and trailer it aims to considerably cut the fuel consumption – and thus also the CO2 emissions of semitrailer tractors at the same time – even further than is currently the case.
Mercedes-Benz also presents a case where even using just some of the components of the Aero Trailer can lead to fuel savings. The side trims panels for example, which cuts wind resistance by 8 percent lead to real-life consumption benefit of some 2 percent for a semitrailer tractor weighing 40 tonnes. That translates to savings of 750 L in a 150,000 km long-distance transport.
Similarly the addition of four flaps measuring just 400 mm in length to the rear of the trailer, and positioned at an angle reduce the wind resistance of the entire semitrailer tractor by nearly ten percent. In arithmetical terms this corresponds to virtually three percent less fuel consumption or more than 1000 l of diesel a year.
All the figures aside, we have to say, the trailer itself looks stunning!