Power exhaust by SOL and pedestal radiation at ASDEX Upgrade and JET

Research output: Contribution to journalArticle

Authors

  • JET Contibutors
  • Dmitry Terentyev
  • Matthias Bernert
  • Marco Wischmeier
  • Alexander F. Huber
  • F. Reimold

Institutes & Expert groups

  • MPI - Max Planck Institute for Iron Research
  • FZJ - Forschungszentrum Jülich GmbH

Documents & links

DOI

Abstract

Future fusion reactors require a safe, steady state divertor operation. A possible solution for the power exhaust challenge is the detached divertor operation in scenarios with high radiated power fractions. The radiation can be increased by seeding impurities, such as N for dominant scrape-off-layer radiation, Ne or Ar for SOL and pedestal radiation and Kr for dominant core radiation. Recent experiments on two of the all-metal tokamaks, ASDEX Upgrade (AUG) and JET, demonstrate operation with high radiated power fractions and a fully-detached divertor by N, Ne or Kr seeding with a conventional divertor in a vertical target geometry. For both devices similar observations can be made. In the scenarios with the highest radiated power fraction, the dominant radiation originates from the confined region, in the case of N and Ne seeding concentrated in a region close to the X-point. Applying these seed impurities for highly radiative scenarios impacts local plasma parameters and alters the impurity transport in the pedestal region. Thus, plasma confinement and stability can be affected. A proper understanding of the effects by these impurities is required in order to predict the applicability of such scenarios for future devices.

Details

Original languageEnglish
Pages (from-to)111-118
Number of pages8
JournalNuclear Materials and Energy
Volume12
DOIs
StatePublished - 27 Jan 2017

Keywords

  • Impurity transport, operation

ID: 5655841