When an airfoil experiences a relatively quick change in angle of attack, a phenomenon called dynamic stall occurs. It basically consists in the formation of a leading edge vortex that grows and travels through the suction side. This impact aerodynamic loads quite dramatically, specially when the vortex is shed. A brief summary of my work on this topic can be seen the in video below. If you want more details about this work, our published paper can be found here, here or here.
An even more in-depth analysis is my MsC thesis (roll the page until the end and click on PDF) , in which I covered some more topics, like modal decomposition with POD (proper orthogonal decomposition) and SPOD (spectral proper orthogonal decomposition).
nice videos!!