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Marie FARGE, Giulio
PELLEGRINO and Kai SCHNEIDER
M.F.: LMD-CNRS, École Normale Supérieure, 24, rue Lhomond,
75231 Paris cedex 05, France;
G.P.: Institut für Chemische Technik, Universität
Karlsruhe (TH), Kaiserstrasse 12, 76128 Karlsruhe, Germany;
K.S.: Centre de Mathématiques
et d'Iinformatique, Université de Provence, 39, rue F. Joliot-Curie,
13453 Marseille cedex 13, France.
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Abstract |
This Letter presents a wavelet technique for extracting coherent
vortices from three-dimensional turbulent flows, which is applied to a homogeneous
isotropic turbulent flow at N=2563. The coherent flow
is reconstructed from only 3%N wavelet coefficients that retain the
vortex tubes, and 98.9%N of the energy with the same k-5/3
spectrum as the total flow. In contrast, the remaining 97%N wavelet
coefficients correspond to the incoherent flow which is structureless, decorrelated,
and whose effect can therfore be modeled statistically.
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