Local and Nonlocal Dispersive Turbulence
| dc.creator | Sukhatme, Jai | |
| dc.creator | Smith, Leslie M. | |
| dc.date | 2007-09-18 | |
| dc.date | 2009-02-20 | |
| dc.date.accessioned | 2026-07-07T12:43:42Z | |
| dc.date.available | 2026-07-07T12:43:42Z | |
| dc.description | We consider the evolution of a family of 2D dispersive turbulence models. The members of this family involve the nonlinear advection of a dynamically active scalar field, the locality of the streamfunction-scalar relation is denoted by $α$, with smaller $α$ implying increased locality. The dispersive nature arises via a linear term whose strength is characterized by a parameter $ε$. Setting $0 < ε\le 1$, we investigate the interplay of advection and dispersion for differing degrees of locality. Specifically, we study the forward (inverse) transfer of enstrophy (energy) under large-scale (small-scale) random forcing. Straightforward arguments suggest that for small $α$ the scalar field should consist of progressively larger eddies, while for large $α$ the scalar field is expected to have a filamentary structure resulting from a stretch and fold mechanism. Confirming this, we proceed to forced/dissipative dispersive numerical experiments under weakly non-local to local conditions. For $ε\sim 1$, there is quantitative agreement between non-dispersive estimates and observed slopes in the inverse energy transfer regime. On the other hand, forward enstrophy transfer regime always yields slopes that are significantly steeper than the corresponding non-dispersive estimate. Additional simulations show the scaling in the inverse regime to be sensitive to the strength of the dispersive term : specifically, as $ε$ decreases, the inertial-range shortens and we also observe that the slope of the power-law decreases. On the other hand, for the same range of $ε$ values, the forward regime scaling is fairly universal. | |
| dc.description | 19 pages, 8 figures. Significantly revised with additional results | |
| dc.identifier | https://arxiv.org/abs/0709.2897 | |
| dc.identifier | http://arxiv.org/abs/0709.2897 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/220510 | |
| dc.subject | Fluid Dynamics | |
| dc.subject | Atmospheric and Oceanic Physics | |
| dc.title | Local and Nonlocal Dispersive Turbulence | |
| dc.type | text |