[Table of Contents]

Plasma and Fusion Research

Volume 7, 2405066 (2012)

Regular Articles

Estimation of Decay Heat in Fusion DEMO Reactor
Youji SOMEYA and Kenji TOBITA
Japan Atomic Energy Agency, Rokkasho-mura, Kamikita-gun, Aomori 039-3212, Japan
(Received 9 December 2011 / Accepted 9 March 2012 / Published 07 June 2012)


The decay heat of activated materials is important in safety assessment of fusion DEMO reactor against loss of coolant-flow accidents. Decay heat for reactor main components of the SlimCS DEMO reactor was studied with a one-dimensional code THIDA-2. The reactor main components consist of the inboard (IB) blanket module, outboard (OB) blanket module and divertor. For a reactor with a fusion output of 3.0 GW, the decay heat of IB blanket, OB blanket, divertor and radiation shield were estimated to be as high as 8.6 MW, 30.9 MW, 10.6 MW and 1.8 MW, respectively, immediately after the shutdown of operation. The total decay heat was as high as 52 MW immediately after the shutdown and 3.1 MW one month later. The blanket produces the largest portion of decay heat, about 76 %.


decay heat, neutronics, safety, DEMO, SlimCS

DOI: 10.1585/pfr.7.2405066


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This paper may be cited as follows:

Youji SOMEYA and Kenji TOBITA, Plasma Fusion Res. 7, 2405066 (2012).