| We discuss single-particle and two-particle statistics in two-dimensional turbulent convection in the Bolgiano--Oboukhov regime by means of high resolution direct numerical simulations. Relative separation of two particles is found to be well described by a generalization of Richardson diffusion model. Single particle velocity structure functions are dominated by large-scale eddies and therefore a careful analysis based on "exit-time" statistics in 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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