Vortex Induced Oscillations of Cylinders

This video shows the orientational behavior of a hinged cylinder suspended in a water tunnel with Reynolds number (Re) ranging between 100-6000 and reduced inertia (I*) in the range 0.1-0.6. The cylinder displays unique features, such as: steady orientation, periodic oscillations and autorotation. We illustrate these features using a phase diagram which captures the observed phenomena as a function of Re and I*. A hydrogen bubble flow visualization technique is employed to show vortex shedding structure in the cylinder?s wake which results in these oscillations.RTG NSF DMS-050226