Numéro |
J. Phys. II France
Volume 7, Numéro 11, November 1997
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Page(s) | 1729 - 1742 | |
DOI | https://doi.org/10.1051/jp2:1997212 |
J. Phys. II France 7 (1997) 1729-1742
Characterization of Turbulence in a Closed Flow
N. Mordant, J.-F. Pinton and F. ChillàÉcole Normale Supérieure de Lyon CNRS URA 1325, 69364 Lyon, France
(Received 29 November 1996, revised 16 June 1997, accepted 16 July 1997)
Abstract
We investigate the closed flow between coaxial contra rotating disks, at moderate to high Reynolds numbers. We show that global
(i.e. spatially averaged) quantities can be used to characterize the state of the flow and its degree of turbulence. We first report
measurements on the driving torque and show how it depends on the manner momentum is imparted to the fluid. We then show that
pressure measurements at the flow boundary provide a good estimate of the rms velocity fluctuations in the flow and that it
reveals the transition to turbulence in the flow volume. Finally, we show that once the transition has occurred, the knowledge
of the same global quantities allows the calculation of fundamental turbulence characteristics such as the rms velocity fluctuations,
the effective integral length scale
L*, Taylor's microscale
and Kolmogorov's dissipation length
. That these quantities may be obtained from measuring devices removed from the bulk of the flow is of importance for the
study of fluid motion in complex geometries and/or using corrosive fluids.
© Les Editions de Physique 1997