The economic and environmental issues related on fuel consumption become gradually a major key point when car manufacturers are designing new vehicles.
Aerodynamic performance is one of the main levers (among other: mass diminution and engine optimization) to improve energetic efficiency of vehicles, since the drag force contributes for a major part of the power consumption for high speed (over 70 km/h). Depending on the exact shape of the vehicle, low-pressure structures can appear at the rear end of the car when the incoming air flow encounters geometric singularities (abrupt change of angle, deflectors, etc.). All these low-pressure structures form a drag force and are responsible of an increase of power consumption.
The collaboration between Groupe PSA and the LFMI laboratory (Pr. François Gallaire) aims at working to a vortex breakdown aerodynamic control: the idea consists in suppressing the low-pressure zone due to highly energetic streamwise vortices that can be found on vehicle with a particular angle of rear-end window.
This collaborative research project takes part in the framework of a PhD thesis between Groupe PSA and the M2P2 laboratory at Marseille and has already led to capture the 3D time-averaged behavior of streamwise vortices on a simplified car. The objective of this research is now to perform a linear stability analysis to obtain suggestions on where and how aerodynamic control should be applied to promote the bursting of such vortices.
|Principal investigator||Prof. François Gallaire|
|Partner||Université de Marseille|