Excitation of Zonal Flow by Intermediate-Scale Toroidal Electron Temperature Gradient Turbulence
Plasma Physics
2021-05-26 v1
Abstract
We show that zonal flow can be preferentially excited by intermediate-scale toroidal electron temperature gradient (ETG) turbulence in tokamak plasmas. Previous theoretical studies that yielded an opposite conclusion assumed a fluid approximation for ETG modes. Here, we carry out a gyrokinetic analysis which ultimately yields a nonlinear Schr\"{o}dinger equation for the ETG dynamics with a Navier-Stokes type nonlinearity. For typical tokamak parameters, it is found that zonal flow generation plays an important role in the intermediate-scale ETG turbulence. This finding offers an explanation for recent multi-scale gyrokinetic simulations.
Keywords
Cite
@article{arxiv.2011.08256,
title = {Excitation of Zonal Flow by Intermediate-Scale Toroidal Electron Temperature Gradient Turbulence},
author = {Haotian Chen and Stefan Tirkas and Scott E. Parker},
journal= {arXiv preprint arXiv:2011.08256},
year = {2021}
}