Annual report of Fusion Research and Development Directorate of JAEA for FY2008 and FY2009

This annual report provides an overview of major results and progress on research and development (R and D) activities at Fusion Research and Development Directorate of Japan Atomic Energy Agency (JAEA) for FY2008 (from April 1, 2008 to March 31, 2009) and FY2009 (from April 1, 2009 to March 31, 2010), including those performed in collaboration with other research establishments of JAEA, research institutes, and universities. Concerning the ITER project, JAEA was nominated as the domestic agency by the Japanese government after the ITER Agreement took effect, and has fulfilled the obligations. In the development of superconducting conductors, JAEA constructed a technical platform for the fabrication of superconducting conductors for toroidal field (TF) coils ahead of other countries. JAEA immediately started and completed the construction of a plant to fabricate superconducting conductors, and started their fabrication ahead of other countries. In the development of gyrotron high-frequency heating equipment, since only the JAEA satisfies the ITER's procurement specifications among supplier countries, the ITER Organization requested JAEA to conduct confidence tests, and achieved results such as data acquisition that could contribute to the development of the ITER's operational scenario. For the development of neutral beam injectors, advantages of the multi-stage acceleration system developed by JAEA was recognized as a result of comparative experiments with single-stage acceleration systems developed in Europe for the particle acceleration system, and was adopted in the ITER's technical specifications. For the Broader Approach (BA) activities, JAEA was designated as the implementing agency by the Japanese government after the BA Agreement took effect, and has fulfilled the obligations and promoted three projects in the BA activities steadily through domestic cooperation and coordination with Europe. Concerning activities related to the International Fusion Energy Research Center, preliminary technological development on R and D issues related to each of low-activation structural materials, SiC/SiC composite materials, tritium technologies, advanced tritium breeder, and advanced neutron multiplier to create DEMO reactors was conducted. In addition, review of conceptual design of DEMO reactors through cooperation with universities and domestic research institutes, and that of selection of the models of super computers to be installed in the Fusion Computer Simulation Center were promoted. In engineering demonstration/design activities for the International Fusion Materials Irradiation Facility (IFMIF), the development of lithium test loop was promoted under cooperation with JAEA's Oarai Research and Development Center which has technologies for liquid metals, and the local construction was started. Besides, design of accelerators was promoted and fabrication of prototypes was started. Concerning activities related to Satellite Tokamak (JT-60SA), integrated design of JT-60SA was completed in Japan and Europe incorporating domestic opinions, and fabrication of superconducting conductors for poloidal field coils was started and procurement activities were promoted in the facilities for fabricating superconducting conductors constructed in Naka Fusion Institute. At the same time, the operation of JT-60 was completed in August 2008 aiming for the establishment of JT-60SA, and preparations for dismantling toward full-scale dismantling and removal are being promoted according to schedule. In addition, the development of the Rokkasho BA site, which will be the center of the BA activities, was also advanced according to schedule, and construction of the DEMO R and D Building, the Computer Simulation and Remote experiment Building, and the IFMIF/EVEDA Accelerator Building, and the central substation was completed as originally planned in March 2010. For research and development on fusion plasma, research on the realization of steady-state and high-beta plasma was promoted, which resulted in success in the world's first sustainment of plasma with a high normalized beta value 3.0, which exceeded the conventional limit (free-boundary ideal stability limit), for approximately 5 seconds. JAEA also joined inter-machine experiments. For research and development on fusion engineering, research and development to construct a technical platform for DEMO reactors was conducted. In the development of breeding blankets, a full-scale mock-up was fabricated and performance demonstration tests were conducted to clarify the fundamental requirements for the ITER Test Blanket Module. In addition, a blanket mock container was fabricated, and neutron irradiation under the same environment as that for actual nuclear fusion reactor blankets was performed at the Fusion Neutronics Source (FNS) facility, where the world's first test to recover tritium generated inside was conducted, demonstrating the achievement of nearly 100% tritium recovery rate for the first time in the world. In research and development on fusion structural materials, the neutron irradiation test of reduced activation ferritic/martensitic steel in HFIR collaboration was continued and irradiation up to 35 dpa was achieved and fundamental data related to corrosion resistance have been accumulated. (author)