Flowfield study of a close-coupled canard configuration

Abstract

A nulling five-hole pressure probe was used to complete a flowfield survey behind a close-coupled canard and wing model set a 32 degrees angle of attack. The canard and wing were both low-aspect-ratio, highly swept, delta platforms with rounded leading edges. The model was set at to condition of maximum life enhancement of the canard/wing configuration over a corresponding wing-alone configuration, based on previous force measurements. For comparison, the pressure measurements were made with the canard on and with the canard off. From the pressure measurements, flowfield velocity-vector, velocity-streamline,, and total pressure coefficient contours were plotted. These plots showed the dramatic effect of the canard vortex on the wing flowfield. The location and interaction of the canard and wing leading edge vortices were analyzed. Large-scale reattachment of previously reversed flow over the wing was noted, as well as the re-establishment and strengthening of the wing leading-edge vortex.