Control of Leading Edge Vortices Using Apex Flap over Non-Slender Delta Wing

Abstract:

This manuscript presents the vortex flow structure over non-slender delta wing with leading edge sweep angle, Λ=45°. A comprehensive investigation has been conducted in wind tunnel at Reynolds number ranging from, Re = 247,000 - 445,000. Seven-hole pressure probe measurements for axial vorticity, axial velocity, vortex trajectory and pressure variations are presented at various chordwise stations and angles of incidences. It was demonstrated that weak leading edge vortices are generated very close to the wing surface with strong shear layer which move upward and outboard with apex flap deflection. Reattachment line move towards wing root chord with the increase in angle of attack. Passive apex flap has been used to control the leading edge vortices and to delay the vortex breakdown. It is recognized that vortex breakdown was delayed by 8% by downward apex flap deflection.

• Periodical: Applied Mechanics and Materials (Volume 390)
• Pages: 12-17
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.390.12
• Online since: August 2013
• Authors: Hafiz Laiq-Ur Rehman
• Keywords: Apex Flap, Leading Edge Vortices, Non-Slender Delta Wing, Vortex Breakdown

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