For inverted wings in close ground proximity, such as race car configurations, the aerodynamic ground effect can produce local velocities significantly greater than the freestream and the effects of compressibility may occur sooner than would be expected for a wing that is not close to a ground plane. A three-dimensional computational fluid dynamics study was conducted, involving a modified NASA GA(W)-2 LS [1]-0413 MOD inverted wing with an endplate, to investigate the onset and significance of compressibility for low subsonic Mach numbers. With the wing angle of incidence fixed, Mach numbers from 0.088 to 0.4 were investigated, at ground clearances ranging from infinite (free flight) to a height-to-chord clearance of 0.067. The freestream Mach number at which flow compressibility significantly affects the predicted aerodynamic coefficients was identified to be as low as 0.15. Beyond this point, as the compressible flow conditions around the wing result in changed pressure distribution and separation behavior, treating the flow as incompressible becomes inappropriate and leads to consistent underprediction of lift and drag. The influence on primary vortex behavior of density changes around the wing was found to be relatively inconsequential even at the higher end of the Mach scale investigated. By a freestream Mach number of 0.4 and at low clearances, local supersonic flow regions were established close to the suction peak of the lower wing surface in compressible simulations; the formation of a normal shock wave between the wing and the ground was shown to result in significant increases in separation and therefore overall drag, as well as a distinct loss of downforce.
Skip Nav Destination
e-mail: t.barber@unsw.edu.au
e-mail: a.neely@adfa.edu.au
Article navigation
June 2011
Research Papers
The Influence of Compressibility on the Aerodynamics of an Inverted Wing in Ground Effect
Tracie J. Barber,
e-mail: t.barber@unsw.edu.au
Tracie J. Barber
Associate Professor
School of Mechanical and Manufacturing Engineering, The University of New South Wales
, Sydney, NSW 2031, Australia
Search for other works by this author on:
Andrew J. Neely
e-mail: a.neely@adfa.edu.au
Andrew J. Neely
Associate Professor
School of Engineering and Information Technology
, The University of New South Wales at the Australian Defence Force Academy, Canberra, ACT 2600, Australia
Search for other works by this author on:
Graham Doig
Research Associate
Tracie J. Barber
Associate Professor
School of Mechanical and Manufacturing Engineering, The University of New South Wales
, Sydney, NSW 2031, Australia
e-mail: t.barber@unsw.edu.au
Andrew J. Neely
Associate Professor
School of Engineering and Information Technology
, The University of New South Wales at the Australian Defence Force Academy, Canberra, ACT 2600, Australia
e-mail: a.neely@adfa.edu.au
J. Fluids Eng. Jun 2011, 133(6): 061102 (12 pages)
Published Online: June 15, 2011
Article history
Received:
July 3, 2010
Revised:
April 25, 2011
Online:
June 15, 2011
Published:
June 15, 2011
Citation
Doig, G., Barber, T. J., and Neely, A. J. (June 15, 2011). "The Influence of Compressibility on the Aerodynamics of an Inverted Wing in Ground Effect." ASME. J. Fluids Eng. June 2011; 133(6): 061102. https://doi.org/10.1115/1.4004084
Download citation file:
Get Email Alerts
Switching Events of Wakes Shed From Two Short Flapping Side-by-Side Cylinders
J. Fluids Eng (May 2025)
Related Articles
Ground Effect Aerodynamics of Race Cars
Appl. Mech. Rev (January,2006)
Aerodynamics of Large-Scale Vortex Generator in Ground Effect
J. Fluids Eng (July,2008)
Analysis of the Vorticity in the Near Wake of a Station Wagon
J. Fluids Eng (February,2017)
Some Aspects of the Aerodynamics of Gurney Flaps on a Double-Element Wing
J. Fluids Eng (March,2001)
Related Proceedings Papers
Related Chapters
Vortex-Induced Vibration
Flow Induced Vibration of Power and Process Plant Components: A Practical Workbook
Applications
Introduction to Finite Element, Boundary Element, and Meshless Methods: With Applications to Heat Transfer and Fluid Flow
Vertical Rise of a Weather Balloon
Case Studies in Fluid Mechanics with Sensitivities to Governing Variables