Self-sustained shock wave oscillations on airfoils and wing at transonic flow conditions are associated with the phenomenon of buffeting. Previous study indicates that the buffet is associated with the interaction between shock wave and separation behind the shock. While supercritical airfoil encountering buffet, there usually exists shock foot separation and trailing edge separation simultaneously. In this paper, we combine rearward bump with upward deflected trailing edge flap, which we called the Hybrid Bumped & Flapped method, to steady or postpone separation at shock foot region and trailing edge region. The study was based on RAE2822 airfoil and DPW-wing 1 supercritical wing which was released on DPW (Drag Prediction Workshop) III. The results show that the rearward bump can obviously weaken the adverse pressure gradient behind the shock and suppress the separation bubble at shock foot merged with the trailing edge separation. The upward deflected flap can effectively postpone the rear separation and eliminate the trailing edge vortex shedding phenomenon at certain conditions. The Hybrid Bumped & Flapped method, consisting of passive contour bump and active deflected flap, has the best effect on buffet control than others. It can steady the position of shock wave and shock foot bubble as well as reduce the instability of rear separation, and finally alleviate the buffet phenomenon and increase the stalling angle.
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