Characteristics of the intense vorticity structures in isotropic turbulence at high Reynolds numbers

Intense vorticity structures (IVS) are known to exist in virtually all turbulent flows, and consist of regions with particularly intense vorticity with (typically) a tubelike shape that keeps its coherence for a relatively long time. We investigated these structures at high Reynolds numbers (Re) using direct numerical simulations (DNS) of isotropic turbulence. The IVS aspect ratio (length to radius) is found to be the same for simulations with very different Re. Since the IVS radius scales with the Kolmogorov microscale, independent of Re, the IVS length at high Re also scales that way, and not with the integral scale or Taylor microscale, as has been suggested in the past.