Browse Publications Technical Papers 2015-01-1544

Fluid Structure Interaction Simulations Applied to Automotive Aerodynamics 2015-01-1544

One of the passive methods to reduce drag on the unshielded underbody of a passenger road vehicle is to use a vertical deflectors commonly called air dams or chin spoilers. These deflectors reduce the flow rate through the non-streamlined underbody and thus reduce the drag caused by underbody components protruding in to the high speed underbody flow. Air dams or chin spoilers have traditionally been manufactured from hard plastics which could break upon impact with a curb or any solid object on the road. To alleviate this failure mode vehicle manufacturers are resorting to using soft plastics which deflect and deform under aerodynamic loading or when hit against a solid object without breaking in most cases. This report is on predicting the deflection of soft chin spoiler under aerodynamic loads. The aerodynamic loads deflect the chin spoiler and the deflected chin spoiler changes the fluid pressure field resulting in a drag change. This fluid structure interaction (FSI) between chin spoiler and the air around it is simulated using coupled fluid and structural solvers. The local and global flow field changes due to FSI and their effect on vehicle drag is discussed. The FSI simulation method is explained and the results compared with test data.


Subscribers can view annotate, and download all of SAE's content. Learn More »


Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:

The Climatic Wind Tunnel of Volkswagenwerk AG


View Details


Control of Interior Pressure Fluctuations Due to Flow Over Vehicle Openings


View Details


Development of “Aero Slit” - Improvement of Aerodynamic Yaw Characteristics for Commercial Vehicles


View Details