The properties of vortex tubes are extracted and analyzed from a DNS database at various Re-lambda, with the objective to characterize the associated distributions of induced velocity and kinetic energy dissipation. The induced velocity exhibits an inverse power-law scaling in the far field, different from Burgers' r(-1) scaling, supporting the interpretation that tubes are the remnants of vortex sheets after roll-up, and suggesting a possible link with the Kolmogorov k(-5/3) spectral scaling. The energy dissipation signature is characterized by a local maximum near the edge of the vortex core, and an absolute peak at its center, which can be tentatively explained appealing to the occurrence of a bi-axial configuration of the strainrate tensor. (C) 2011 Elsevier B.V. All rights reserved.
On the velocity and dissipation signature of vortex tubes in isotropic turbulence / Pirozzoli, Sergio. - In: PHYSICA D-NONLINEAR PHENOMENA. - ISSN 0167-2789. - 241:3(2012), pp. 202-207. [10.1016/j.physd.2011.03.005]
On the velocity and dissipation signature of vortex tubes in isotropic turbulence
PIROZZOLI, Sergio
2012
Abstract
The properties of vortex tubes are extracted and analyzed from a DNS database at various Re-lambda, with the objective to characterize the associated distributions of induced velocity and kinetic energy dissipation. The induced velocity exhibits an inverse power-law scaling in the far field, different from Burgers' r(-1) scaling, supporting the interpretation that tubes are the remnants of vortex sheets after roll-up, and suggesting a possible link with the Kolmogorov k(-5/3) spectral scaling. The energy dissipation signature is characterized by a local maximum near the edge of the vortex core, and an absolute peak at its center, which can be tentatively explained appealing to the occurrence of a bi-axial configuration of the strainrate tensor. (C) 2011 Elsevier B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
