Laboratory model of two-dimensional polar beta-plane turbulence
The evolution of a two-dimensional turbulent decaying flow is experimentally analyzed in a rotating system considering the effect of the change of the Coriolis force with latitude. The flow is generated using an electro-magnetic (EM) cell, i.e., by electro-magnetically forcing a thin layer of a saline solution, in a rotating reference frame. A Feature Tracking (FT) technique is used to measure the flow field allowing the reconstruction of high resolution velocity and vorticity fields. In agreement with theoretical prediction and previous experiments, results corresponding to high values of the beta parameter show a preferential transfer of energy towards zonal modes and the consequent organization of a weak anticyclonic circulation in the polar zone. Moreover, the analysis of the one-dimensional energy spectra shows a scaling steeper than Kolmogorov’s law and a peak near the Rhines scale indicating a soft barrier of the energy transfer towards low wave-numbers.
KeywordsVortex Anisotropy Depression Vorticity Styrene
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- P.B. Rhines, Waves and turbulence on a beta plane, JFM 69, 417 (1975)Google Scholar
- P.B. Rhines, Jets 4, 313 (1994)Google Scholar
- J. Pedlosky, Geophysical Fluid Dynamics, Springer, (1979)Google Scholar
- M. Miozzi, Particle Image Velocimetry using Feature Tracking and Delauny Tessellation, Proceedings of the 12th International Symposium “Application of laser techniques to fluid mechanics”, Lisbon, (2004)Google Scholar
- P. Tabeling, Two dimensional turbulence: a physicist approach, Phys. Reports 1, 362 (2002)Google Scholar
- B.D. Lucas, T. Kanade, An iterative image registration technique with an application to stereo vision, Proceedings of Imaging Understanding Workshop, 121 (1981)Google Scholar
- J. Shi, C. Tomasi, Good features to track, In Proceedings of IEEE Conference on Computer Vision and Pattern Recognition, (1994)Google Scholar
- A. Cenedese, S. Espa, M. Miozzi, Experimental study of two-dimensional turbulence using Feature Tracking, Proc. 12th International Symposium “Application of laser techniques to fluid mechanics”, Lisbon, (2004)Google Scholar
- Carnevale, G.F. 2006 Mathematical and Physical Theory of Turbulence John Cannon and Sen Shivamoggi (Eds.) Taylor and FrancisGoogle Scholar