Measurement of particle and bubble accelerations in turbulence - ENS de Lyon - École normale supérieure de Lyon Access content directly
Preprints, Working Papers, ... Year : 2007

Measurement of particle and bubble accelerations in turbulence

Romain Volk
  • Function : Author
  • PersonId : 842064
Gautier Verhille
Jean-François Pinton
  • Function : Author
  • PersonId : 830908

Abstract

We use an extended laser Doppler technique to track optically the velocity of individual particles in a high Reynolds number turbulent flow. The particle sizes are of the order of the Kolmogorov scale and the time resolution, 30 microseconds, resolves the fastest scales of the fluid motion. Particles are tracked for mean durations of the order of 10 Kolmogorov time scales. The fastest scales of the particle motion are resolved and the particle acceleration is measured. For neutrally buoyant particles, our measurement matches the performance of the silicon strip detector technique introduced at Cornell University~\cite{Voth,MordantCornell}. This reference dynamics is then compared to that of slightly heavier solid particles (density 1.4) and to air bubbles. We observe that the acceleration variance strongly depends on the particle density: bubbles experience higher accelerations than fluid particles, while heavier particles have lower accelerations. We find that the probability distribution functions of accelerations normalized to the variance are very close although the air bubbles have a much faster dynamics.
Fichier principal
Vignette du fichier
ELDV_submit.pdf (68.82 Ko) Télécharger le fichier
Origin Files produced by the author(s)

Dates and versions

ensl-00167302 , version 1 (18-08-2007)

Identifiers

Cite

Romain Volk, Nicolas Mordant, Gautier Verhille, Jean-François Pinton. Measurement of particle and bubble accelerations in turbulence. 2007. ⟨ensl-00167302⟩
151 View
76 Download

Altmetric

Share

Gmail Mastodon Facebook X LinkedIn More