Aerodynamic Characteristics and Topology of Interfering Vortex Systems at Hybrid-Delta Wings

Abstract

High-agility aircraft often perform flight maneuvers at high angles of attack and angles of sideslip. For these configurations, a comprehension of the vortex development, interaction, and breakdown at sideslip conditions is crucial. In this study, two generic, low-aspect-ratio, hybrid-delta-wing configurations are investigated. A triple-delta-wing and a double-delta-wing configuration are discussed. Force and moment measurements, particle image velocimetry, and oil-flow visualization tests are conducted to resolve the vortex-dominated flowfield extensively. The flow separates at the sharp leading edges, and vortices are formed. For an angle of sideslip, the effective leading-edge sweep on the windward side is reduced and on the leeward side increased. This leads to a more stable vortex system on the leeward side and a destabilization on the windward side. Therefore, significant lateral instabilities occur at high angles of attack.