Lagrangian statistics in two-dimensional free turbulent convection
نویسندگان
چکیده
We discuss single-particle and two-particle statistics in twodimensional turbulent convection in the Bolgiano–Oboukhov regime by means of high-resolution direct numerical simulations. Relative separation of two particles is found to be described well by a generalization of the Richardson diffusion model. Single-particle velocity structure functions are dominated by large-scale eddies and therefore a careful analysis based on ‘exit-time’ statistics is necessary to identify turbulent contributions. Because the velocity field is not intermittent, small-scale acceleration statistics is found to be in good agreement with simple dimensional predictions.
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