Optimizing the aerodynamics of heavy goods vehicles by modifying their underbody
The shape and dimensions of freight vehicles are subject to significant legal constraints. Little optimized, their aerodynamic profile is responsible for an increase in fuel consumption. Any external modification of heavy goods vehicles in favor of aerodynamics must be compatible with traffic regulations.
Researchers at the Institute of Aerodynamics and Fluid Mechanics (IAS) of the German Aerospace Research Center (DLR) in Göttingen (Lower Saxony) are developing aerodynamic solutions by modifying the undercarriage of heavy goods vehicles. "Due to the pressure difference at the front and rear of the truck, a force opposite to the direction of travel appears with a suction effect", explains Johannes Haff, researcher at IAS. "By modifying the bedrock by widening its rear section, similar to a diffuser, the pressure behind on the conveyor could be increased by the generation of vortices in the direction of flow, with the consequence of reducing the flow rate. 'suction effect,' he continues.
These improvements have already been successfully tested in the wind tunnel. To confirm these, DLR researchers carried out road tests at night by combining pressure sensors on the rear wall of the truck with the particle image velocimetry (PIV) technique [1]. To this end, a laser system, measuring devices, computers and a smoke generator have been loaded on board a 40-ton truck. High resolution CCD cameras were attached to the back of the truck. The latter traveled the test track at different speeds, collecting data series currently in operation.
For more information, contact:
- [1] More information on the particle image velocimetry technique (in French): http://www.onera.fr/conferences/mesures ... 16-piv.php
- Johannes Haff, researcher at the Institute of Aerodynamics, Fluid Mechanics and Fluid Systems at the DLR Center in Göttingen - tel. : +49 551 709-2140 - email: Johannes.Haff@dlr.de
Source:
http://www.bulletins-electroniques.com/ ... /70605.htm
It seems to me that there are already things in the field (we had talked about it) ... but I no longer have any idea of the names (a kind of fin) ... Someone may remember be?