c © TÜB_ITAK Eect of Pitching Delta Wing on Vortex Structures with and

Flow past the leading edge of a delta wing oscillating about its mid-cord in a pitch plane with a reduced frequency of K=0.74 generates primary vortices having mostly elongated shapes. Their shapes and orienta-tions vary with the pitching angle of the delta wing in upstroke and downstroke directions. Unsteady flows around the impingement plate placed downstream of the delta wing and in the flow eld downstream of the onset of vortex breakdown are characterized by the existence of unsteady large-and small-scale vortices. These time-dependent vortex core formations and breakdowns apply aerodynamic loads to the impingement plate. For the pitching delta wing, the development of the vortex core and degree of hysteresis are found to be a strong function of reduced frequency