Dynamics of fully nonlinear drift wave-zonal flow turbulence system in plasmas
Abstract
We present numerical simulations of fully nonlinear drift wave-zonal flow (DW-ZF) turbulence systems in a nonuniform magnetoplasma. In our model, the drift wave (DW) dynamics is pseudo-three-dimensional (pseudo-3D) and accounts for self-interactions among finite amplitude DWs and their coupling to the two-dimensional (2D) large amplitude zonal flows (ZFs). The dynamics of the 2D ZFs in the presence of the Reynolds stress of the pseudo-3D DWs is governed by the driven Euler equation. Numerical simulations of the fully nonlinear coupled DW-ZF equations reveal that short scale DW turbulence leads to nonlinear saturated dipolar vortices, whereas the ZF sets in spontaneously and is dominated by a monopolar vortex structure. The ZFs are found to suppress the cross-field turbulent particle transport. The present results provide a better model for understanding the coexistence of short and large scale coherent structures, as well as associated subdued cross-field particle transport in magnetically confined fusion plasmas.
- Publication:
-
Physics Letters A
- Pub Date:
- December 2009
- DOI:
- 10.1016/j.physleta.2009.10.059
- arXiv:
- arXiv:0910.1635
- Bibcode:
- 2009PhLA..374..286S
- Keywords:
-
- 52.35.Kt;
- 52.35.Mw;
- 52.25.Fi;
- 52.35.Ra;
- Drift waves;
- Nonlinear phenomena: waves wave propagation and other interactions;
- Transport properties;
- Plasma turbulence;
- Physics - Plasma Physics;
- Physics - Computational Physics
- E-Print:
- To appear in Physics Letter A