TY - JOUR
T1 - Japan’s Efforts to Develop the Concept of JA DEMO During the Past Decade
AU - The Joint Special Design Team for Fusion DEMO
AU - Tobita, Kenji
AU - Hiwatari, Ryoji
AU - Sakamoto, Yoshiteru
AU - Someya, Youji
AU - Asakura, Nobuyuki
AU - Utoh, Hiroyasu
AU - Miyoshi, Yuya
AU - Tokunaga, Shinsuke
AU - Homma, Yuki
AU - Kakudate, Satoshi
AU - Nakajima, Noriyoshi
N1 - Funding Information:
This work was carried out in the framework of the activity of the Joint Special Design Team for Fusion DEMO and partly by the DEMO Design Activity under the Broader Approach (BA). We would like to express cordial gratitude to experts of Institutes for Quantum and Radiological Science and Technology (QST), National Institute for Fusion Science (NIFS), universities, and manufacturing companies for their valuable advice and helpful support to the Special Design Team. The authors also acknowledge members of the EUROfusion PPPT Team for stimulating discussion in BA DEMO design activities. This work was partly supported by KAKENHI Grant-in-Aid for Scientific Research (C), No. 17K07002.
Publisher Copyright:
© 2019, © 2019 The Author(s). Published with license by Taylor & Francis Group, LLC.
PY - 2019/7/4
Y1 - 2019/7/4
N2 - This paper summarizes the evolution of Japanese DEMO design studies in a retrospective manner by highlighting efforts to resolve critical design issues on DEMO. Japan is currently working on the conceptual study of a steady-state DEMO (JA DEMO) with a major radius Rp of 8.5 m and fusion power Pfus of 1.5 to 2 GW based on water-cooled solid breeding blanket with pressurized water reactor water condition (290ºC to 325ºC, 15.5 MPa). Such a lower Pfus allows to find realistic design solutions for divertor heat removal. Recognizing that divertor heat removal is one of the most challenging issues on DEMO, the divertor design has been carried out in different approaches, including numerical divertor plasma simulation, magnetic configurations, heat sink design, etc. It is noteworthy that the latest divertor simulation led to a design window allowing divertor heat removal of the peak heat flux of <10 MW/m2. The breeding blanket (BB) design has been concentrated on simplification of the internal structure and pressure tightness of the BB casing against the in-box loss-of-coolant accident. Due to a large amount of radioactive waste generated in periodic replacement of in-vessel components, downsizing of waste-related facilities has come to be regarded as a significant design issue. A possible waste management for reducing temporary waste storage was proposed, and its impact on the plant layout was assessed.
AB - This paper summarizes the evolution of Japanese DEMO design studies in a retrospective manner by highlighting efforts to resolve critical design issues on DEMO. Japan is currently working on the conceptual study of a steady-state DEMO (JA DEMO) with a major radius Rp of 8.5 m and fusion power Pfus of 1.5 to 2 GW based on water-cooled solid breeding blanket with pressurized water reactor water condition (290ºC to 325ºC, 15.5 MPa). Such a lower Pfus allows to find realistic design solutions for divertor heat removal. Recognizing that divertor heat removal is one of the most challenging issues on DEMO, the divertor design has been carried out in different approaches, including numerical divertor plasma simulation, magnetic configurations, heat sink design, etc. It is noteworthy that the latest divertor simulation led to a design window allowing divertor heat removal of the peak heat flux of <10 MW/m2. The breeding blanket (BB) design has been concentrated on simplification of the internal structure and pressure tightness of the BB casing against the in-box loss-of-coolant accident. Due to a large amount of radioactive waste generated in periodic replacement of in-vessel components, downsizing of waste-related facilities has come to be regarded as a significant design issue. A possible waste management for reducing temporary waste storage was proposed, and its impact on the plant layout was assessed.
KW - DEMO
KW - blanket
KW - diverter
KW - fusion reactor
KW - radioactive waste
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U2 - 10.1080/15361055.2019.1600931
DO - 10.1080/15361055.2019.1600931
M3 - Article
AN - SCOPUS:85065469934
VL - 75
SP - 372
EP - 383
JO - Fusion Science and Technology
JF - Fusion Science and Technology
SN - 1536-1055
IS - 5
ER -