Chaotic flow generated by an oscillating foil

A numerical code developed by Guglielmini and Blondeaux was used to simulate the flow generated by the oscillating foil in hovering mode. It was found that when the foil simply oscillates in the transverse direction with no rotation, small amplitudes of the oscillations give rise to a periodic flow. A chaotic flow was observed by increasing the amplitude of the oscillation. Short simulations indicated that the transition to chaos takes place according to the quasi-periodicity and phase-locking scenario. However, longer simulations show that the qausi-periodic regime was a transient unstable feature that give rise to a chaotic dynamics.