Leading-Edge Radius Effects on Aerodynamic Characteristics of 50-Degree Delta Wings

The experimental study focuses on the effects of the leading-edge radius on the flow over 50 deg swept delta wing models. Three models were tested; one model has a sharp leading edge, and two others have a semicircular leading edge of a different radius. Six-component balance measurements were performed and indicated that the leading-edge radius affects the level and slope of the forces acting on the models. The vortical flow on and off the surface of the models was investigated using an oil flow visualization and a stereo particle image velocimetry technique. The leading-edge radius is shown to affect the location, size, and strength of the vortices and also the vortex breakdown location over the models. The flow data are correlated with the balance data.