Statistical properties of Charney-Hasegawa-Mima zonal flows
Artikel i vetenskaplig tidskrift, 2015

A theoretical interpretation of numerically generated probability density functions (PDFs) of intermittent plasma transport events in unforced zonal flows is provided within the Charney- Hasegawa-Mima (CHM) model. The governing equation is solved numerically with various prescribed density gradients that are designed to produce different configurations of parallel and anti-parallel streams. Long-lasting vortices form whose flow is governed by the zonal streams. It is found that the numerically generated PDFs can be matched with analytical predictions of PDFs based on the instanton method by removing the autocorrelations from the time series. In many instances, the statistics generated by the CHM dynamics relaxes to Gaussian distributions for both the electrostatic and vorticity perturbations, whereas in areas with strong nonlinear interactions it is found that the PDFs are exponentially distributed.

Statistical properties of flows

Charney-Hasegawa-Mima

Zonal flows

Författare

Johan Anderson

Chalmers, Rymd- och geovetenskap, Plasmafysik och fusionsenergi

Gert J J Botha

Northumbria University

Physics of Plasmas

1070-664X (ISSN) 1089-7674 (eISSN)

Vol. 22 052305 052305

Ämneskategorier

Fysik

Fusion, plasma och rymdfysik

Styrkeområden

Energi

Fundament

Grundläggande vetenskaper

DOI

10.1063/1.4919852