Sharp vorticity gradients in two-dimensional hydrodynamic turbulence
| dc.creator | Kuznetsov, E. A. | |
| dc.creator | Naulin, V. | |
| dc.creator | Nielsen, A. H. | |
| dc.creator | Rasmussen, J. Juul | |
| dc.date | 2004-07-19 | |
| dc.date.accessioned | 2026-07-07T05:52:19Z | |
| dc.date.available | 2026-07-07T05:52:19Z | |
| dc.description | The appearance of sharp vorticity gradients in two-dimensional hydrodynamic turbulence and their influence on the turbulent spectra is considered. We have developed the analog of the vortex line representation as a transformation to the curvilinear system of coordinates moving together with the di-vorticity lines. Compressibility of this mapping can be considered as the main reason for the formation of the vorticity discontinuities at high Reynolds numbers. For two-dimensional turbulence in the case of strong anisotropy the vorticity discontinuities can generate spectra with the fall-off at large $k$ proportional to $k^{-3}$ resembling the Kraichnan spectrum for the enstrophy cascade. For turbulence with weak anisotropy the $k$ dependence of the spectrum due to discontinuities coincides with that of the Saffman spectrum: $k^{-4}$. We have compared the analytical predictions with direct numerical solutions of the two-dimensional Euler equation for decaying turbulence. We observe that the di-vorticity is reaching very high values and is distributed locally in space along piecewise straight lines. Thus, indicating strong anisotropy and accordingly we found a spectrum close to the $k^{-3}$-spectrum. | |
| dc.description | 24 pages, 6 figures | |
| dc.identifier | https://arxiv.org/abs/physics/0407101 | |
| dc.identifier | http://arxiv.org/abs/physics/0407101 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/86284 | |
| dc.subject | Fluid Dynamics | |
| dc.title | Sharp vorticity gradients in two-dimensional hydrodynamic turbulence | |
| dc.type | text |