Europhys. Lett.
Volume 71, Number 4, August 2005
Page(s) 590 - 596
Section Electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics
Published online 13 July 2005
Europhys. Lett., 71 (4), pp. 590-596 (2005)
DOI: 10.1209/epl/i2005-10111-6

Effects of friction on 2D turbulence: An experimental study of the direct cascade

G. Boffetta1, A. Cenedese2, S. Espa2 and S. Musacchio3

1  Dipartimento di Fisica Generale and INFN, Università degli Studi di Torino Via Pietro Giuria 1, I-10125 Torino, Italy
2  Dipartimento di Idraulica, Trasporti e Strade, Università "La Sapienza" Via Eudossiana 18, I-00184 Roma, Italy
3  Dipartimento di Fisica, Università "La Sapienza" P.le A. Moro 2, I-00185 Roma, Italy

received 24 March 2005; accepted in final form 9 June 2005
published online 13 July 2005

We study the direct enstrophy cascade in a two-dimensional flow generated in an electromagnetically driven thin layer of fluid. Due to the presence of bottom friction, the energy spectrum deviates from the classical Kraichnan prediction k-3. We find that the correction to the spectral slope depends on the thickness on the layer, in agreement with a theoretical prediction based on the analogy with passive scalar statistics.

47.27.Gs - Isotropic turbulence; homogeneous turbulence.
47.52.+j - Chaos.

© EDP Sciences 2005