Impact of plasma-wall interaction and exhaust on the EU-DEMO design

• DOI: 10.1016/j.nme.2020.100897
• Publication Date: 2021-01-10T10:49:17Z
• Authors: F. Maviglia; M. Siccinio; C. Bachmann; W. Biel; M. Cavedon; E. Fable; G. Federici; M. Firdaouss; J. Gerardin; V. Hauer; I. Ivanova-Stanik; F. Janky; R. Kembleton; F. Militello; F. Subba; S. Varoutis; C. Vorpahl
• Keywords: Limiter; Fusion power

In the present work, role of plasma facing components protection in driving EU-DEMO design will be reviewed, focusing on steady-state and, especially, transients. This work encompasses both first wall (FW) as well divertor. fact, while ITER divertor heat removal technology has been adopted, FW concept shown past years to inadequate for EU-DEMO. is due higher foreseen irradiation damage level, which requires structural materials (like Eurofer) able withstand more than 5 dpa neutron damage. solution, however, limits tolerable flux ~1 MW/m2, i.e. a factor 3–4 below specifications. For this reason, poloidally and toroidally discontinuous limiters are implemented Their consists reducing load charged particles, during steady state importantly, planned off-normal Concerning configuration, currently assumes an ITER-like, lower single null (LSN) divertor, with seeded impurities dissipation power. However, by numerous simulations marginal (where detached necessary maintain technological limit avoid excessive erosion) unable some relevant transients, such large ELMs accidental loss detachment. Various concepts, deviating from design, under investigation mitigate risks, example in-vessel coils strike point sweeping case reattachment, alternative configurations. Finally, broader discussion impact overall machine presented.