Direct measurements of the energy of intense vorticity filaments in turbulence.

Phys Rev E Stat Nonlin Soft Matter Phys

Laboratoire de Mécanique, Université du Havre, 25 Rue Philippe Lebon, 76058 Le Havre Cedex, France.

Published: February 2003

The global instantaneous power injected in a turbulent shear flow is investigated. A conditional averaging technique reveals the complete energetic transfer scenario of the intense vorticity filaments, which were visualized by Douady, Couder, and Brachet [Phys. Rev. Lett. 67, 983 (1991)]. It is found that during their existence filaments store a significant part of the turbulent kinetic energy. This energy is dissipated during the destruction phase of filaments. The total energy transferred to small scales due to filaments is quantified on the basis of a global flow visualization.

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http://dx.doi.org/10.1103/PhysRevE.67.027301DOI Listing

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