Volume 115, Number 3, August 2016
|Number of page(s)||6|
|Section||Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics|
|Published online||07 September 2016|
Fourier signature of filamentary vorticity structures in two-dimensional turbulence
1 Departamento de Fisica, Universidad Carlos III de Madrid - Leganes 28911, Spain
2 Physics Department, University of Alaska - Fairbanks AK 99775, USA
3 University of Wisconsin-Madison - Madison, WI 53706, USA
Received: 20 June 2016
Accepted: 16 August 2016
It is shown that coherent regions of isotropic two-dimensional (2D) turbulence can be clearly identified in the phase part of the Fourier spectrum. Certain spectral phase events are particularly prominent, and are much stronger in the range of wave numbers corresponding to the dissipation range. It is shown that these events are associated with spatially localized filamentary structures in the 2D vorticity field that historically have been related to the intermittency of dissipation. The identified phase signature provides a particularly transparent diagnostic of the temporal evolution of the coherent coupling of disparate scales in anisostropic intermittent dissipative events. These results open the possibility of using the phase of the Fourier transform as a new turbulence diagnostic that identifies and quantitatively characterizes details pertaining to dissipative events.
PACS: 47.27.De – Coherent structures / 47.27.Gs – Isotropic turbulence; homogeneous turbulence / 47.27.E- – Turbulence simulation and modeling
© EPLA, 2016
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.