Next Article in Journal
Tailoring the Chemistry of Plasma-Activated Water Using a DC-Pulse-Driven Non-Thermal Atmospheric-Pressure Helium Plasma Jet
Next Article in Special Issue
Amplitude Modulation And Nonlinear Self-Interactions of the Geodesic Acoustic Mode at the Edge of MAST
Previous Article in Journal
Acinetobacter baumannii Deactivation by Means of DBD-Based Helium Plasma Jet
Open AccessArticle

Computing the Double-Gyroaverage Term Incorporating Short-Scale Perturbation and Steep Equilibrium Profile by the Interpolation Algorithm

1
Institut de Recherche Mathématique Avancée, 7 rue René Descartes, 67084 Strasbourg CEDEX & Inria TONUS Team, France
2
Aix Marseille Univ, CNRS, Centrale Marseille, I2M, Marseille, France
*
Author to whom correspondence should be addressed.
Plasma 2019, 2(2), 91-126; https://doi.org/10.3390/plasma2020009
Received: 6 February 2019 / Revised: 3 April 2019 / Accepted: 3 April 2019 / Published: 9 April 2019
(This article belongs to the Special Issue Magnetic Confinement Fusion)
In the gyrokinetic model and simulations, when the double-gyroaverage term incorporates the combining effect contributed by the finite Larmor radius, short scales of the perturbation, and steep gradient of the equilibrium profile, the low-order approximation of this term could generate unignorable error. This paper implements an interpolation algorithm to compute the double-gyroaverage term without low-order approximation to avoid this error. For a steep equilibrium density, the obvious difference between the density on the gyrocenter coordinate frame and the one on the particle coordinate frame should be accounted for in the quasi-neutrality equation. A Euler–Maclaurin-based quadrature integrating algorithm is developed to compute the quadrature integral for the distribution of the magnetic moment. The application of the interpolation algorithm to computing the double-gyroaverage term and to solving the quasi-neutrality equation is benchmarked by comparing the numerical results with the known analytical solutions. Finally, to take advantage of the interpolation solver clearer, the numerical comparison between the interpolation solver and a classical second order solver is carried out in a constant theta-pinch magnetic field configuration using SELALIB code. When the equilibrium profile is not steep and the perturbation only has the non-zero mode number along the parallel spatial dimension, the results computed by the two solvers match each other well. When the gradient of the equilibrium profile is steep, the interpolation solver provides a bigger driving effect for the ion-temperature-gradient modes, which possess large polar mode numbers. View Full-Text
Keywords: electrostatic gyrokinetic model; double-gyroaverage term; interpolation algorithm; euler–maclaurin quadrature integrating formula electrostatic gyrokinetic model; double-gyroaverage term; interpolation algorithm; euler–maclaurin quadrature integrating formula
Show Figures

Figure 1

MDPI and ACS Style

Zhang, S.; Mehrenberger, M.; Steiner, C. Computing the Double-Gyroaverage Term Incorporating Short-Scale Perturbation and Steep Equilibrium Profile by the Interpolation Algorithm. Plasma 2019, 2, 91-126.

Show more citation formats Show less citations formats

Article Access Map by Country/Region

1
Back to TopTop