Superstatistical mechanics of tracer-particle motions in turbulence.
The Lagrangian stochastic model of Reynolds [Phys. Fluids 15, L1-4 (2003)]] for the accelerations of fluid particles in turbulence is shown to predict precisely the observed Reynolds-number dependency of the distribution of Lagrangian accelerations and the exponents characterizing the observed extended self-similarity scaling of the Lagrangian velocity structure functions. Departures from superstatistics of the log-normal kind are accounted for and their impact upon model predictions is quantified.
Reynolds
A M
AM
Silsoe Research Institute, Wrest Park, Silsoe, Bedford MK45 4HS, United Kingdom.