A closure model for intermittency in three dimensional incompressible turbulence
Abstract
A simplified Lagrangean closure for the Navier-Stokes equation is used to study the production of intermittency in the inertial range of three dimensional turbulence. This is done using localized wavepackets following the fluid rather than a standard Fourier basis. In this formulation, the equation for the energy transfer acquires a noise term coming from the fluctuations in the energy content of the different wavepackets. Assuming smallness of the intermittency correction to scaling allows the adoption of a quasi-gaussian approximation for the velocity field, provided a cutoff on small scales is imposed and a finite region of space is considered. In this approximations, the amplitude of the local energy transfer fluctuations, can be calculated self consistently in the model. Definite predictions are obtained on the scaling of the wavepacket energy moments.
Cite
@article{arxiv.chao-dyn/9411018,
title = {A closure model for intermittency in three dimensional incompressible turbulence},
author = {Piero Olla},
journal= {arXiv preprint arXiv:chao-dyn/9411018},
year = {2009}
}
Comments
Plain tex source code; file in ascii format; 24 pages 6 figures and 1 table (not included); table and figures available directly from author; send e-mail to: [email protected]