Rare Event-Triggered Transitions in Aerodynamic Bifurcation

The transitions between two states of a bistable system are investigated experimentally and analyzed in the framework rare-event statistics. Considering disk pendulum swept by flow wind tunnel, bistability aerodynamic branches is observed, with spontaneous from one branch to other. waiting times before transition distributed following double-exponential as function control parameter, spanning four orders magnitude time, for both transitions. Inspired model originally applied turbulence, we show that, pendulum, controlled rare events forces acting on which propose link particular vortex shedding-induced fluctuations. Beyond aspects, this work has interesting fundamental outcomes regarding broad field out-of-equilibrium systems.