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Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Fusion Science and Technology
Latest News
Zaporizhzhia ‘extremely fragile’ relying on single off-site power line, IAEA warns
Europe’s largest nuclear power plant has just one remaining power line for essential nuclear safety and security functions, compared with its original 10 functional lines before the military conflict with Russia, warned Rafael Mariano Grossi, director general of the International Atomic Energy Agency.
M.E. Friend, C.B. Baxi, S. Ishida, G. Kurita, E.E. Reis, A. Sakasai, W.P. West
Fusion Science and Technology | Volume 39 | Number 2 | March 2001 | Pages 923-929
Divertor and Plasma-Facing Components | doi.org/10.13182/FST01-A11963358
Articles are hosted by Taylor and Francis Online.
General Atomics recently completed a divertor design study for JAERI for the JT-60 Super Upgrade (JT-60SU) tokamak. JT-60SU is being designed as a superconducting device for an integrated R&D investigation of steady-state operation in a tokamak. A divertor design was developed to accommodate double-null operation for a 1000 s discharge duration at 8 MA of plasma current and 80 MW of auxiliary heating. The work reported here is an extension of a previous design study.1,2 The thermal requirements are a peak heat flux of 9 MW/m2, a maximum surface temperature of 1600°C, and a poloidal cooling flow configuration for the plasma facing components. The structural requirements are determined from both the predicted stresses due to halo currents as well as the stresses due to differential thermal expansion encountered during bakeout. The halo current loads are based on a nominal halo current of 0.19 Ip with a 2.0 toroidal peaking factor. Analysis has determined that the halo current load per centimeter of circumference is P = 2856 (1+cosθ) N/cm, where θ is the toroidal angle. The loads due to differential thermal expansion are a result of an expected 100°C temperature difference between the vacuum vessel and divertor during bakeout.
Based on the aforementioned criteria, a divertor design was developed for all three areas of the JT-60SU divertor: the inner baffle, the private flux baffle, and the outer baffle. In order to have highly reliable divertor components, flexible supports sized to accommodate the structural loads are utilized in the design rather than insulators or sliding interfaces. The plasma facing components are mounted on a structural mounting plate to form a removable and remotely-maintainable segment which is in turn mounted on the supports. For outer and private flux baffles, these structural mounting plates are joined together using a double shear joint design to form a structurally continuous ring to react the halo current loads. The plasma facing components are broken into 8° segmentation; however, the outer and private flux baffles have an alternating 8° and 16° structural segmentation which forms the double shear toroidal structural joint. The inner baffle takes advantage of its relatively short poloidal length and its proximity to the vacuum vessel to provide structural integrity. The thermal design consists of a plasma facing material of flat CFC tiles that are brazed onto a poloidally cooled copper heat sink. Adequate gaps between the baffles and wall are provided for pumping of recycled gas.
