Particle and heat flux measurements from XGC1 simulations: Spatial patterns and SOL width implications.

POSTER

Abstract

Strong turbulence near the separatrix is believed to produce filamentary structures (blobs), whose detachment from the bulk can account for the intermittent nature of edge turbulence and impact the heat flux width. The SOL width is a parameter of paramount importance in modern tokamaks as it controls the amount of power deposited at the divertor plates, directly affecting thus the viability of fusion. Here, we analyze the results of simulations performed with the full-f, gyrokinetic code XGC1 which includes both turbulence and neoclassical effects in realistic divertor geometry. More specifically, we calculate the integrated particle and heat fluxes across the separatrix and present their spatial pattern. The flux is impacted by neoclassical effects and ExB turbulent-blobby motion. We isolate the ExB turbulent flux and estimate its contribution to the SOL width. Furthermore, we offer an interpretation of the observed patterns, tying them to the sheared perpendicular and parallel flows.

*We acknowledge computing resources on Titan at OLCF through the 2015 INCITE and the 2016 ALCC awards. Work supported by DOE grant DE-FG02-97ER54392.

Authors

  • Ioannis Keramidas Charidakos

    • University of Colorado at Boulder
  • J.R. Myra

    • Lodestar Research Corporation
    • Lodestar Research
    • Lodestar
  • Scott Parker

    • University of Colorado at Boulder
    • Univ. Colorado Boulder
    • Univ of Colorado - Boulder
    • Dept. of Physics, Univ. of Colorado, Boulder
  • Seung-Hoe Ku

    • Princeton Plasma Phys Lab
    • Princeton Plasma Physics Laboratory
    • PPPL
  • Jugal Chowdhury

    • Princeton Plasma Physics Laboratory
  • R.M. Churchill

    • PPPL
    • Princeton Plasma Physics Laboratory
    • Princeton Plasma Physics laboratory
  • Robert Hager

    • Princeton Plasma Phys Lab
    • PPPL
    • Princeton Plasma Physics Laboratory
    • Princeton Plasma Physics laboratory
  • Choong-Seock Chang

    • Princeton Plasma Phys Lab
    • Princeton Plasma Physics Laboratory
    • PPPL
    • Princeton Plasma Physics laboratory