Abstract : Following the Kolmogorov technique, an exact relation for a vector third-order moment J is derived for three-dimensional incompressible stably stratified turbulence under the Boussinesq approximation. In the limit of a small Brunt-Vaisala frequency, isotropy may be assumed which allows us to find a generalized 4/3-law. For strong stratification, we make the ansatz that J is directed along axisymmetric surfaces parameterized by a scaling law relating horizontal and vertical coordinates. An integration of the exact relation under this hypothesis leads to a generalized Kolmogorov law which depends on the intensity of anisotropy parameterized by a single coefficient. By using a scaling relation between large horizontal and vertical length scales we fix this coefficient and propose a unique law.
https://hal-polytechnique.archives-ouvertes.fr/hal-00996508
Contributor : Denis Roura
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Submitted on : Thursday, June 5, 2014 - 2:20:39 PM
Last modification on : Friday, May 10, 2019 - 1:21:34 AM
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Pierre Augier, Sebastien Galtier, Paul Billant. Kolmogorov laws for stratified turbulence. Journal of Fluid Mechanics, Cambridge University Press (CUP), 2012, 709, pp.659-670. ⟨10.1017/jfm.2012.379⟩. ⟨hal-00996508⟩
