The ground-effect diffuser has become a major aerodynamic device on open-wheel racing and sports cars. Accordingly, it is widely considered to be indispensable to their aerodynamic performance, largely due to its significant downforce contribution. However, the physics and characteristics that determine how it generates downforce and its application in the auto racing industry require an in-depth analysis to develop an understanding. Furthermore, research that could generate further performance improvement of the diffuser has not been defined and presented. For these reasons, this review attempts to create a systematic understanding of the physics that influence the performance of the ground-effect diffuser. As a means of doing this, the review introduces research data and observations from various relevant studies on this subject. It then investigates advanced diffuser concepts mainly drawn from the race car industry and also proposes a further research direction that would advance the aerodynamic performance of the diffuser. It is concluded that although the diffuser will continue to be paramount in the aerodynamic performance of racing cars, research is needed to identify means to further enhance its performance.
A Review of Ground-Effect Diffuser Aerodynamics
Contributed by the Fluids Engineering Division of ASME for publication in the JOURNAL OF FLUIDS ENGINEERING. Manuscript received September 28, 2017; final manuscript received June 1, 2018; published online June 29, 2018. Assoc. Editor: Daniel Maynes.
Ehirim, O. H., Knowles, K., and Saddington, A. J. (June 29, 2018). "A Review of Ground-Effect Diffuser Aerodynamics." ASME. J. Fluids Eng. February 2019; 141(2): 020801. https://doi.org/10.1115/1.4040501
Download citation file: