| Numéro |
J. Phys. II France
Volume 7, Numéro 5, May 1997
|
|
|---|---|---|
| Page(s) | 801 - 812 | |
| DOI | https://doi.org/10.1051/jp2:1997152 | |
J. Phys. II France 7 (1997) 801-812
Sound Scattering on a Turbulent, Weakly Heated Jet
A. Petrossian1, 2 and J.-F. Pinton11 Laboratoire de Physique, École Normale Supérieure de Lyon CNRS URA 1325, 69364 Lyon France
2 Physics Department, Yerevan State University, 1 Manoukian street, 375049 Yerevan, Armenia
(Received 28 October 1996, revised 22 January 1997, accepted 13 February 1997)
Abstract
We report an experimental study of the scattering of ultrasonic plane waves on a turbulent jet in air (Pr = 0.7). The jet
is weakly heated so that the temperature fluctuations act as a passive scalar. In the backscattering geometry one measures
the Fourier components of the temperature field
. The time averaged characteristics are analyzed in detail; in particular we observe a Kolmogorov "-5/3" power law behavior
for the passive scalar spectrum in the inertial range of scales. The study of the time fluctuations shows that the histograms
of
remain close to a Gaussian at all scales.
© Les Editions de Physique 1997