Investigation of Delta Wing Leading-Edge Devices

Abstract

Leading-edge flow manipulators for alleviating the subsonic lift-dependent drag of highly-swept wings were investigated experimentally. The potential of several devices—fences, chordwise slots, pylon vortex generators, and a vortex plate concept—was evaluated in wind tunnel tests on a 60 deg cropped delta wing research model. Simultaneous balance and pressure measurements at increasing angles of attack provided an insight into the spanwise leading-edge flow development and its modification by the devices. The results demonstrated significant drag reductions through partial recovery of leading-edge suction at elevated angles of attack. In most cases, improvement in longitudinal stability also was obtained.