CCFE PR1603

Fusion Engineering and Design 109–111 (2016) 917–924 Contents lists available at ScienceDirect Fusion Engineering and Design jo ur nal home p age: www.elsevier.com/locate/fusengdes Progress in the engineering design and assessment of the European DEMO first wall and divertor plasma facing components Thomas R. Barretta,∗, G. Ellwooda, G. Péreza, M. Kovaria, M. Fursdona, F. Domptaila, S. Kirka, S.C. McIntosha, S. Robertsa, S. Zhenga, L.V. Boccaccinib, J.-H. Youc, C. Bachmannd, J. Reisere, M. Riethe, E. Viscaf, G. Mazzonef, F. Arbeiterb, P.K. Domalapallyg aCCFE, Culham Science Centre, Abingdon OX14 3DB, United Kingdom bKIT, INR, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany cMax Planck Institute for Plasma Physics, Boltzmannstr. 2, 85748 Garching, Germany dEUROfusion, PPPT, Boltzmann Str. 2, 85748 Garching, Germany eKIT, IAM, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany fENEA, Unità Tecnica Fusione, ENEA C. R. Frascati, via E. Fermi 45, 00044 Frascati, Italy gResearch Center Rez, Hlavní 130, 250 68 Husinec –Rˇezˇ, Czech Republic h i g h l i g h t s • The engineering of the plasma facing components for DEMO is an extreme challenge. • PFC overall requirements, methods for assessment and designs status are described. • Viable divertor concepts for 10 MW/m2surface heat flux appear to be within reach. • The first wall PFC concept will need to vary poloidally around the wall. • First wall coolant, structural material and PFC topology are open design choices. a r t i c l e i n f o Article history: Received 31 August 2015 Received in revised form 21 January 2016 Accepted 25 January 2016 Available online 11 February 2016 Keywords: EUROfusion DEMO Plasma-facing a component Design b s t r a c t The European DEMO power reactor is currently under conceptual design within the EUROfusion Con- sortium. One of the most critical activities is the engineering of the plasma-facing components (PFCs) covering the plasma chamber wall, which must operate reliably in an extreme environment of neutron irradiation and surface heat and particle flux, while also allowing sufficient neutron transmission to the tritium breeding blankets. A systems approach using advanced numerical analysis is vital to realising viable solutions for these first wall and divertor PFCs. Here, we present the system requirements and describe bespoke thermo-mechanical and thermo-hydraulic assessment procedures which have been used as tools for design. The current first wall and divertor designs are overviewed along with sup- porting analyses. The PFC solutions employed will necessarily vary around the wall, depending on local conditions, and must be designed in an integrated manner by analysis and physical testing. © 2016 EURATOM/CCFE Fusion Association. Published by Elsevier B.V. All rights reserved. 1. Introduction The European DEMO power reactor is currently under concep- tual design in the framework of the EUROfusion Consortium. This is a long-pulsed tokamak device demonstrating the technologies required for commercial exploitation of fusion and with a physics basis which is a realistic extrapolation from ITER [1,2]. The current ∗ Corresponding author. E-mail address: [email protected] (T.R. fundamental Barrett). plasma parameters, derived from system codes, are major radius ∼9 m, aspect ratio 3.1 and a relatively low plasma normalised pressure of ˇ ∼ N 2.5 giving a fusion power output of 2 GW . th Unlike any fusion device existing today, the reactor will be required to be self-sufficient in the breeding of tritium fuel, must demonstrate the potential for efficient power production, and must safely operate under high fluence 14 MeV irradiation and extreme particle fluxes [3]. As a result of these requirements, one of the most critical activities in the design of DEMO is the engineering of the plasma-facing components (PFCs) that cover the tokamak chamber interior. http://dx.doi.org/10.1016/j.fusengdes.2016.01.052 0920-3796/© 2016 EURATOM/CCFE Fusion Association. Published by Elsevier B.V. All rights reserved.