Title

Implications of compressibility effects for Reynolds-scaled testing of an inverted wing in ground effect

Author Info

G. Doig, University of New South WalesFollow
Tracie J. Barber, University of New South Wales
Sammy Diasinos, Macquarie University

Recommended Citation

Postprint version. Published in International Journal of Aerodynamics, Volume 4, Issue 3/4, January 1, 2014, pages 135-153.

NOTE: At the time of publication, the author G. Doig was not yet affiliated with Cal Poly.

Abstract

The influence of compressibility around an isolated inverted wing at a fixed Reynolds number was examined as relevant to the issue of wind tunnel scaling effects. Three-dimensional simulations were conducted for low ground clearances, at: full scale and a Mach number of 0.088, at 50% scale at Mach 0.176, and at 25% scale at Mach 0.352. As the scale was reduced, the increasing peak local Mach number between the wing and the ground resulted in a higher propensity of the flow to separate towards the trailing edge, and for incompressible or full-scale CFD to underestimate the lift and drag coefficients by an ever-increasing margin. The lower vortex path was less affected. The results suggest that compressible CFD of a scale experiment ought to be conducted at the same Reynolds number and Mach number as the tunnel test for the best possible correlation at free-stream Mach numbers beyond 0.15.

Disciplines

Aerospace Engineering

Copyright

Inderscience Publishers.