After the implementation of higher standards for the maximum exhaust emission of a modern passenger car a challenge for the next years could be the implementation of emission regularities in the truck industry. Reducing the fuel consumption is one way to reduce emissions and can be regarded as one of today’s most urgent issues that need to be addressed by engineers. Besides, the imminent energy scarcity will result in rising total cost for fuel consumption. Hence the reduction of these costs is a significant economic aspect for the transport sector.Due to the fact that aerodynamic drag is responsible for more than 20% of the total energy losses of a modern tractor-trailer the aerodynamic optimization of the vehicle geometry would provide a crucial portion for energy savings.The predominant part of aerodynamic drag of such bluff bodies is generated by the wake field behind the trailer which is characterised by three-dimensional and instationary flow structures. Since many decades the reduction of aerodynamic drag of heavy vehicles is part of investigations of science and industry where a wide range of passive and active methods were developed. The German Aerospace Center (DLR) in Göttingen performs experimental investigations of the aerodynamics of heavy vehicles to understand the flow phenomena and to deliver new concepts for the reduction of aerodynamic drag.
1/15th scale truck model in the cryogenic wind tunnel of DNW in Cologne