A high-accuracy Euleriangyrokinetic solver for collisional plasmas

JOURNAL OF COMPUTATIONAL PHYSICS

卷:324

Article

Candy, J.¹  Belli, E. A.¹  Bravenec, R. V.² 

[1] Gen Atom Co, POB 85608, San Diego, CA 92186 USA

[2] Fourth State Res, Austin, TX 78704 USA

关键词: Gyrokinetic;    Eulerian;    Continuum;   

DOI  :  10.1016/j.jcp.2016.07.039

来源: Elsevier

【 摘 要 】

We describe a new approach to solve the electromagnetic gyrokinetic equations which is optimized for accurate treatment of multispecies Fokker-Planck collisions including both pitch-angle and energy diffusion. The new algorithm is spectral/pseudospectral in four of the five phase space dimensions, and in the fieldline direction a novel 5th-order conservative upwind scheme is used to permit high-accuracy electromagnetic simulation even in the limit of very high plasma beta and vanishingly small perpendicular wavenumber, k(perpendicular to) -> 0. To our knowledge, this is the first pseudospectral implementation of the collision operator in a gyrokinetic code. We show that the new solver agrees closely with GYRO in the limit of weak Lorentz collisions, but gives a significantly more realistic description of collisions at high collision frequency. The numerical methods are also designed to be efficient and scalable for multiscale simulations that treat ion-scale and electron-scale turbulence simultaneously. (C) 2016 Elsevier Inc. All rights reserved.

【 授权许可】

Free