Proposal for an alternative type of helium-cooled blanket for DEMO

• Published in: Fusion engineering and design Vol. 41; no. 1; pp. 569 - 575
• Main Authors: Zacchia, F, Cerullo, N, Fossa, C
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01.09.1998; New York, NY Elsevier Science
• Subjects: Applied sciences; Controled nuclear fusion plants; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Installations for energy generation and conversion: thermal and electrical energy; Nuclear fusion reactor; Blanket; Gas release; Cooling system; Thermohydraulics; Tritium; Helium; Performance; Vanadium alloy; Research and development
• ISSN: 0920-3796; 1873-7196
• DOI: 10.1016/S0920-3796(98)00143-4

In this paper, an attempt to modify the blanket design proposed and analysed by the CEA in the framework of DEMO, featuring Li–Pb as breeder-multiplier and water as coolant, is presented. The aim of the proposed modifications is to improve the safety and tritium breeding performances of the blanket by the use of helium instead of water, and by the substitution of the martensitic steel structural material by a vanadium alloy. The existing geometry and the general hydraulic configuration are maintained in the breeding zones and in the first wall: the former is cooled by poloidal single-wall U-bent tubes, and the latter by toroidal–radial oriented tubes buried in the first wall panels and fed by headers located behind the back plate. Neutronic calculations have been brought forward in order to evaluate the volumetric power deposition and the tritium production (TBR). Due to the harder neutron spectrum a 30% Li-6 enrichment seems to be adequate. Thermal hydraulic calculations show that the selected helium parameters are standard ones for modern plants.