Vortex Induced Oscillations of Cylinders

The submitted fluid dynamics videos [1] depict the various orientational dynamics of a hinged cylinder suspended in a flow tank. The different behaviors displayed by the cylinder range from steady orientation to periodic oscillation and even autorotation. We illustrate these features using a phase diagram which captures the observed phenomena as a function of Reynolds number (Re) and reduced inertia (I∗). A hydrogen bubble flow visualization technique is also used to show vortex shedding structure in the cylinders wake which results in these oscillations.