Gyrokinetic Large Eddy Simulations

TL;DR

This paper adapts the Large Eddy Simulation approach to gyrokinetic plasma turbulence, introducing a sub-grid scale model that effectively reproduces key spectral features in ion temperature gradient driven turbulence.

Contribution

It presents a novel LES framework for gyrokinetic simulations, including a simple dissipative sub-grid scale model calibrated for plasma turbulence.

Findings

The sub-grid scale model reproduces the free energy spectra accurately.

Reduced resolution simulations with the model match full-resolution results.

The approach offers a computationally efficient way to study plasma microturbulence.

Abstract

The Large Eddy Simulation (LES) approach is adapted to the study of plasma microturbulence in a fully three-dimensional gyrokinetic system. Ion temperature gradient driven turbulence is studied with the {\sc GENE} code for both a standard resolution and a reduced resolution with a model for the sub-grid scale turbulence. A simple dissipative model for representing the effect of the sub-grid scales on the resolved scales is proposed and tested. Once calibrated, the model appears to be able to reproduce most of the features of the free energy spectra for various values of the ion temperature gradient.