Colloquium: Pere Valls Badia (FPT)

Inspired by the leading-edge protuberances found on the flippers of humpback whales, tubercles have drawn significant interest for improving airfoil aerodynamic performance. In static conditions, airfoils with tubercles exhibit a softer onset of stall and increased lift in post-stall regime, though with a reduced maximum lift coefficient. However, their impact under dynamic conditions is less understood, particularly how they affect the formation and convection of the dynamic stall vortex (DSV), which is crucial to the dynamic stall process. This study employs Particle Tracking Velocimetry (PTV) and Computational Fluid Dynamics (CFD) to investigate the influence of tubercles on the DSV. The findings indicate that tubercles modify the onset and severity of dynamic stall by reducing the strength of the DSV and shifting its formation closer to the trailing-edge. These changes result in a weaker and shorter lift overshoot, enabling a quicker transition to deep stall, where tubercles provide more lift.

Supervisor: Morgan Li