Fully implicit particle-in-cell simulation of gyrokinetic electromagnetic modes in XGC1 without the cancellation issue

POSTER

Abstract

Electromagnetic gyrokinetic simulation of tokamak plasma has been suffering from the so-called “cancellation problem,” in which the long wavelength modes make the simulation blow up. Recently, a fully implicit electromagnetic Vlasov-Darwin particle-in-cell algorithm using fluid preconditioner is developed [1]. We adopt this scheme to XGC1, a 5D total-f gyrokinetic code. For the parallel velocity, v|| is used instead of the canonical momentum p||. Picard iteration is used with fluid pre-conditioner. Subcycling of particle motions and fixed-point accelerator raise the simulation efficiency. The cancellation problem does not appear even in the longest wavelength Alfven wave range (n=0, m=1) at tokamak plasma βe values. Kinetic ballooning and micro-tearing modes will be discussed for NSTX and other tokamak plasmas.

[1] G. Chen, L. Chacon, Comput. Phy. Comm. 185, 2391 (2014)

*Funded by US DOE FES and ASCR, and computing resources provided by OLCF through INCITE.

Presenters

  • Seung Hoe Ku

    • Princeton Plasma Physics Laboratory
    • Princeton Plasma Phys Lab
    • Princeton Plasma Physics Laboratory, Princeton, NJ 08543-451, USA

Authors

  • Seung Hoe Ku

    • Princeton Plasma Physics Laboratory
    • Princeton Plasma Phys Lab
    • Princeton Plasma Physics Laboratory, Princeton, NJ 08543-451, USA

  • Benjamin J Sturdevant

    • Princeton Plasma Physics Laboratory
    • Princeton Plasma Phys Lab

  • Robert Hager

    • Princeton Plasma Physics Laboratory
    • Princeton Plasma Physics Lab
    • Princeton Plasma Physics Laboratory, Princeton, NJ 08543-451, USA
    • Princeton Plasma Phys Lab

  • Choong Seock Chang

    • Princeton Plasma Physics Laboratory
    • Princeton Plasma Physics Lab
    • Princeton Plasma Phys Laboratory
    • Princeton Plasma Phys Lab
    • Princeton Plasma Physics Laboratory, Princeton, NJ 08543-451, USA

  • Luis Chacon

    • Los Alamos National Laboratory
    • Los Alamos Natl Lab

  • Guangye Chen

    • Los Alamos Natl Lab