Description
Drift wave turbulence in magnetically confined plasmas plays a crucial role in the self-organization of macroscopic structures, such as zonal flows, which are essential for regulating turbulent transport. In addition to these flows, turbulence can spontaneously form long-lived isolated vortices. Recent basic plasma experiments have suggested that these isolated vortices significantly contribute to the driving mechanism of zonal flows. However, a comprehensive theoretical and numerical understanding of this process remains to be fully established.
In this study, we investigate the autonomous generation of isolated vortices and their interaction with shear flows using two-dimensional numerical simulations based on the Hasegawa-Wakatani model. Our results successfully reproduce the emergence of coherent vortex structures within the turbulent field. We perform a quantitative analysis to evaluate the Reynolds stress and the kinetic energy transfer associated with these vortices. The presentation will focus on quantifying the specific role of isolated vortices in sustaining zonal flows and provide a comparative discussion with observations from basic laboratory experiments.