학술논문

Variational formulation of the Germano identity for the Navier–Stokes equations.
Document Type
Article
Source
Journal of Turbulence. 2005, Vol. 6 Issue 7, p1-17. 17p.
Subject
*STOKES equations
*PARTIAL differential equations
*EDDY currents (Electric)
*EDDY flux
*EDDIES
*TURBULENCE
*RHEOLOGY
Language
ISSN
1468-5248
Abstract
The variational counterpart of the Germano identity for the large eddy simulation (LES) of turbulent flows is derived. The differences between the variational and the filter-based identities are explained on the basis of the role of an LES model in these two formulations. The variational Germano identity is then used to determine parameters in LES models. The performance of this identity in predicting the Smagorinsky eddy viscosity during the decay of homogeneous isotropic turbulence is evaluated. It is found that it yields results that are as accurate as its filter-based counterpart and that it is less sensitive to the exact approach used in evaluating the unknown parameters. [ABSTRACT FROM AUTHOR]