2DESR: a two-dimensional Fourier-space gyrokinetic eigenvalue code for the ion-temperature-gradient modes in tokamaks

TL;DR

The paper introduces 2DESR, a new 2D gyrokinetic eigenvalue solver for ITG modes in tokamaks, accurately capturing full ion kinetic effects and benchmarking well against existing codes.

Contribution

The development of 2DESR provides a novel, efficient tool for solving 2D gyrokinetic eigenvalue problems in tokamaks, including full ion kinetic effects.

Findings

2DESR accurately benchmarks against GENE and NLT.

Two branches of ITG modes coexist in the system.

Full ion kinetic effects are retained in the solver.

Abstract

A two-dimensional (2D) gyrokinetic eigenvalue solver, 2DESR, has been developed to solve the 2D gyrokinetic eigenvalue problem in the poloidal Fourier space for the ion-temperature-gradient (ITG) modes in tokamaks. With full kinetic effects of ions retained, the 2D gyrokinetic eigenvalue equations in the poloidal Fourier space have been derived and numerically solved in the 2DESR code. In the linear ITG Cyclone test with adiabatic electrons, the 2DESR code benchmarks well against the gyrokinetic initial-value codes GENE and NLT. It is found that two branches of ITG modes coexist in the system.