AERODYNAMIC ANALYSIS OF WING WITH LEADING EDGE PROTUBERANCES USING PRANDTL’S LIFTING LINE THEORY

Abstract

The establishment of active or passive flow control techniques over aircraft wings has been an area of continuous effort of experimental as well as theoretical investigations. The passive flow control method of leading edge modification has proven to be effective in improving the lift performance of a wing. Extensive performance analysis of sinusoidal tubercles and the wavy wing has been conducted in the literature. This work aims to determine whether other leading edge geometric modifications like square and triangular protrusions similar to sinusoidal tubercles can provide the same effects. The aerodynamic performance of the wings with sinusoidal, square, and triangular tubercles with amplitudes of 3 mm, 5 mm, 7 mm, and 9 mm and wavelengths of 8 mm, 16 mm, 32 mm, and 64 mm is investigated using Prandtl’s lifting line theory. The effect of wavelength and amplitude variation on lift coefficient (C<inf>L</inf>) and coefficient of induced drag (C<inf>Di</inf>) is studied within the prestall regime. The results have shown that C<inf>L</inf> and C<inf>Di</inf> reduce and the ratio of these coefficients (C<inf>L</inf>/C<inf>Di</inf>) improves for the tubercled wing when compared to the baseline wing. The effect of wavelength variation is found to be negligible. In contrast, amplitude variation showed a maximum increase of C<inf>L</inf>/C<inf>Di</inf> in the wing with square tubercles, where it reached 305.15 at 1° AoA, for an amplitude of 9 mm. © 2022 by Begell House, Inc.