CONTROL OF HIGH-INCIDENCE VORTICAL FLOW ON DOUBLE-DELTA WINGS UNDERGOING SIDESLIP

An experimental study of the vortical now over a baseline double-delta wing model and a diamond-fillet double-delta wing model, both with sh arp leading edges, was conducted in a water tunnel using the dye-injec tion technique at a nominal now Reynolds number of 1.875 x 10(4). The diamond fillets at the strake/wing junction increased the wing area of the baseline model by 1%. The main focus of this study was to evaluat e the effect of juncture fillets on the vortex core trajectory and the vortex burst location at high angles of attack with sideslip angle. C omparison of the test results between the baseline and the diamond-fil let models indicates a clear delay for the latter model in terms of bo th the vortex core trajectory, and the breakdown location at high angl e of attack, with sideslip angles, The vortex breakdown data for the d iamond-fillet model implies lift augmentation during sideslip motion, thus supporting the concept of how control using fillets, From the man euvering viewpoint, the data suggest that the diamond-fillet model has a better operational envelope.