Study on a new method for suppression of vertical tail buffeting using inflatable bumps

This paper investigates a new method to suppress buffeting using an inflatable bump through numerical simulation. An inflatable bump is mounted appropriately close to the apex, along the vortex core on the suction surface, because it can be reshaped rapidly by inflating. When the angle of attack is small, the bump is not inflated and vortex lift, dependent on vortex intensity, is not affected. When severe buffeting begins at high angles of attack, the bump can be inflated instantly and then a bulge appears. The bulge will weaken the vortex intensity, change the vortex position, and reduce the unsteady aerodynamic load on the tail in the separated flow after the vortex breakdown, thus the goal of buffeting suppression is achieved. Numerical simulation for a delta-wing, twin tail layout demonstrates that the inflatable bump twists the path-line of the vortex core, weakens the vortex core intensity, and shifts the vortex breakdown position closer to the apex at high angles of attack. The moment coefficient about the left tail root is decreased significantly, the pressure fluctuation is reduced on the tail surface, and the peak of power spectral density is lessened, too. In conclusion, this kind of inflatable bump is a convenient and reliable way to suppress buffeting, and further investigation should be conducted.