A stochastic representation of the local structure of turbulence
Based on the mechanics of the Euler equation at short time, we show that a Recent-Fluid-Deformation (RFD) closure for the vorticity field, neglecting the early stage of advection of fluid particles, allows to build a 3D incompressible velocity field that shares many properties with empirical turbule...
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Published in | Europhysics letters Vol. 89; no. 5; pp. 54002 - 54007 |
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Main Authors | , , |
Format | Journal Article |
Language | English |
Published |
IOP Publishing
01.03.2010
EDP Sciences |
Subjects | |
Online Access | Get full text |
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Summary: | Based on the mechanics of the Euler equation at short time, we show that a Recent-Fluid-Deformation (RFD) closure for the vorticity field, neglecting the early stage of advection of fluid particles, allows to build a 3D incompressible velocity field that shares many properties with empirical turbulence, such as the teardrop shape of the RQ-plane. Unfortunately, non-Gaussianity is weak (i.e., no intermittency) and vorticity gets preferentially aligned with the wrong eigenvector of the deformation. We then show that slightly modifying the former vectorial field in order to impose the long-range–correlated nature of turbulence allows to reproduce the main properties of stationary flows. Doing so, we end up with a realistic incompressible, skewed and intermittent velocity field that reproduces the main characteristics of 3D turbulence in the inertial range, including correct vorticity alignment properties. |
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Bibliography: | ark:/67375/80W-H2G003ZL-B publisher-ID:epl12527 istex:B4BFF3065DBCCD97FE1397E6FBF68EC2BB16329D ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 |
ISSN: | 0295-5075 1286-4854 |
DOI: | 10.1209/0295-5075/89/54002 |