FLOWFIELD STUDY OF A CLOSE-COUPLED CANARD CONFIGURATION

A wind-tunnel study was completed examining the flowfield behavior of the canard-vortex/wing-vortex interaction for a close-coupled canard c onfiguration in the post-stall regime. Three cross-planes were mapped in the lee flowfield using a five-hole pressure probe. The mappings tr aced the canard and wing vortices as they moved downstream, and gave c lear evidence that the canard vortex provided the mechanism for flow r eattachment over the inboard wing section. The previously separated fl ow became a coherent wing leading-edge vortex under the canard vortex influence. A tertiary vortex at the canard-fuselage juncture was revea led; this vortex may have an impact upon the resulting flow, and would not be evident in studies of bodiless wings with canards. Surface flo w visualization aided in revealing the effects of the post-stall behav ior.