Saturation Level of ETG Turbulence
Paper i proceeding, 2013

In this work the finite β-effects of an electron branch of the geodesic acoustic mode (el-GAM) driven by electron temperature gradient (ETG) modes is presented. The work is based on a fluid description of the ETG mode retaining nonadiabatic ions and the dispersion relation for el-GAMs driven non-linearly by ETG modes is derived. The ETG growth rate from the fluid model is compared to the results found from gyrokinetic simulations with good agreement. A new saturation mechanism for ETG turbulence through the interaction with el-GAMs is found, resulting in a significantly enhanced ETG turbulence saturation level compared to the mixing length estimate. It is shown that the el-GAM may be stabilized by an increase in finite β as well as by increasing non-adiabaticity. The decreased GAM growth rates is due to the inclusion of the Maxwell stress.

Författare

Johan Anderson

Chalmers, Teknisk fysik, Nukleär teknik

Hans Nordman

Chalmers, Rymd- och geovetenskap

Chalmers, Rymd- och geovetenskap, Plasmafysik och fusionsenergi

Raghvendra Singh

Festival de Thorie

Vol. 7 4-

Styrkeområden

Energi

Fundament

Grundläggande vetenskaper

Ämneskategorier

Fusion, plasma och rymdfysik