On the decay of a turbulent vortex ring

The spatiotemporal evolution of a turbulent vortex ring with an initial Reynolds number of 7500 is experimentally investigated using the technique of digital particle image velocimetry. The flow is initially characterized by the laminar/turbulent transition via azimuthal bending instabilities. After transition, the shedding of vorticity from peripheral regions of the ring is found to be responsible for the formation of a wake region. This shedding process results in the staircase-like decay of the circulation and propagation speed of the vortex ring.