22nd Congress of International Council of the Aeronautical Sciences, Harrogate, UK, 28 August - 1st September, 2000
Paper ICAS 2000-3.7.5

DRAG, LIFT AND PITCHING MOMENT INCREMENTS DUE TO THE WIND TUNNEL WALL CONSTRAINT : EXTENSION TO THREE DIMENSIONS

J. E. Hackett (1), K. R. Cooper (2), M. L. Perry (1)
(1) Lockheed Martin Aeronautics Company, Marietta, Georgia, USA; (2) National Research Council, Ottawa, Canada.

Keywords: drag, lift, pitch, moments, wall constraints, wind-tunnel, three-dimensions

Wind-tunnel-induced flow distortion around a test model causes drag, lift and pitching moment increments that are absent in free air. Previous two-dimensional predictions of these effects are extended to three dimensions and means for evaluating them are discussed. A new extension to Maskell's blockage prediction method, designated "Maskell III", is introduced that estimates the lift increment. Other boundary correction approaches include procedures based on the use of wall pressure measurements and the application of pressure signature and two-variable algorithms. These studies are supported by dedicated experiments on a family of flat plate wings, carried out at the NRC. Initial applications of the new correction methods to these data have produced encouraging results.

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