Intermittency of Velocity Time Increments in Turbulence

Laurent Chevillard (1) , Stéphane G. Roux (1) , Emmanuel Lévêque (1) , Nicolas Mordant (2) , Jean-François Pinton (1) , Alain Arnéodo (1)

1 Phys-ENS - Laboratoire de Physique de l'ENS Lyon
2 LPS - Laboratoire de Physique Statistique de l'ENS

We analyze the statistics of turbulent velocity fluctuations in the time domain. Three cases are computed numerically and compared: (i) the time traces of Lagrangian fluid particles in a (3D) turbulent flow (referred to as the dynamic case); (ii) the time evolution of tracers advected by a frozen turbulent field (the static case); (iii) the evolution in time of the velocity recorded at a fixed location in an evolving Eulerian velocity field, as it would be measured by a local probe (referred to as the virtual probe case). We observe that the static case and the virtual probe cases share many properties with Eulerian velocity statistics. The dynamic (Lagrangian) case is clearly different; it bears the signature of the global dynamics of the flow.

Mots clés: Turbulence; Lagrangian

Domaines: Dynamique des Fluides [physics.flu-dyn]

Laurent Chevillard, Stéphane G. Roux, Emmanuel Lévêque, Nicolas Mordant, Jean-François Pinton, et al.. Intermittency of Velocity Time Increments in Turbulence. Physical Review Letters, 2005, 95 (1), pp.064501. ⟨ensl-00180594⟩