arXiv 1001.29952010-01-18nlin.CDphysics.flu-dyn

Nonlinear diffusion model for Rayleigh-Taylor mixing

G. Boffetta, F. De Lillo, S. Musacchio

备注：: 4 pages, 4 figure, PRL in press
DOI：: 10.1103/PhysRevLett.104.034505

英文摘要：

The complex evolution of turbulent mixing in Rayleigh-Taylor convection is studied in terms of eddy diffusiviy models for the mean temperature profile. It is found that a non-linear model, derived within the general framework of Prandtl mixing theory, reproduces accurately the evolution of turbulent profiles obtained from numerical simulations. Our model allows to give very precise predictions for the turbulent heat flux and for the Nusselt number in the ultimate state regime of thermal convection.

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