Recent activities on optimizing the base design of LHD-type helical reactor FFHR2ml is presented. Three candidates to secure the blanket space are proposed in the direction of reactor size optimization without deteriorating -heating efficiency and with taking cost analyses into account. For this direction the key engineering aspects are investigated; on 3D blanket designs, it is shown that the peaking factor of neutron wall loading is 1.2 to 1.3 and the blanket cover rate over 90％ is possible by proposing Discrete Pumping with Semi-closed Shield (DPSS) concept.
Akio Sagara H. Tamura N. Yanagi K. Nishimura H. Chikaraishi S. Yamada S. Fukada A. Shishkin T. Watanabe Y. Igitkhanov T. Goto O. Mitarai Y. Ogawa T. Muroga T. Mito O. Motojima S. Imagawa T. Tanaka Y. Kozaki M. Kobayashi T. Morisaki S. Masuzaki K. Takahata
National Institute for Fusion Science, Toki, Gifu 509-5292, Japan Kyushu University, 6-10-1 Hakozaki, Fukuoka, Fukuoka 812-8581, Japan Kharkov Institute of Physics and Technology, Kharkov-108, Ukraine Max-Planck-Institut fur Plasmaphysik, IPP-EURATOM Ass., Greifswald, Germany The University of Tokyo, 5-1-5 Kashiwa, Chiba 277-8568, Japan Kyushyu Tokai University, 9-1-1 Toroku, Kumamoto 862-8652, Japan