Turbulence Fluctuations and New Universal Realizability Conditions in Modelling
Gregory L. Eyink, Francis J. Alexander
Abstract
General turbulent mean statistics are shown to be characterized by a variational principle. The variational functionals, or ``effective actions'', have experimental consequences for turbulence fluctuations and are subject to realizability conditions of positivity and convexity. An efficient Rayleigh-Ritz algorithm is available to calculate approximate effective actions within PDF closures. Examples are given for Navier-Stokes and for a 3-mode system of Lorenz. The new realizability conditions succeed at detecting a priori the poor predictions of PDF closures even when the classical 2nd-order moment realizability conditions are satisfied.
Create a lesson
Related papers
Chaotic eigenfunctions in phase space
S. Nonnenmacher, A. Voros
Improved control of delayed measured systems
Jens Christian Claussen, Heinz Georg Schuster
The accurate and comprehensive model of thin fluid flows with inertia on curved substrates
A. J. Roberts, Zhenquan Li
On periodic solutions of a Hamilton-Jacobi equation with periodic forcing
Andrei Sobolevskii
Drifters dispersion in the Adriatic Sea: Lagrangian data and chaotic model
Guglielmo Lacorata, Erik Aurell, Angelo Vulpiani
Generalized multibaker maps for open dissipative systems
Z. Kaufmann, P. Szépfalusy