Aerodynamic characteristics and topology of interfering vortex systems at hybrid-delta wings

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 flow field 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.