Vortex shedding, or von Karman vortex street, as it is sometimes known, has been around for many years. It is a phenomenon in fluid mechanics for a repeating pattern of swirling vortices caused by the unsteady separation of liquids or gases over bluff bodies. It is vortex shedding that causes singing in the telephone wires, or causes flags to flutter, as the vortices are shed from the flagpole.