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Division Spotlight
Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
Standards Program
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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Latest News
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Mohamed A. Abdou, Jungchung Jung
Nuclear Technology | Volume 35 | Number 1 | August 1977 | Pages 51-79
Technical Paper | Reactor | doi.org/10.13182/NT77-A31850
Articles are hosted by Taylor and Francis Online.
Detailed nuclear analysis of a reference conceptual design for a tokamak experimental power reactor (EPR) is presented. The reference EPR has a 6.25-m major radius and a 2.1-m minor radius circular plasma with a nominal neutron wall loading of 0.5 MW/m2. A 0.28-m-thick blanket of stainless steel surrounds a stainless-steel vacuum vessel. The inner shield consists of stainless steel and B4C and is 0.58 m thick. The 0.97-m-thick outer shield employs lead mortar, stainless steel, and graphite. The neutronics results in the first wall and blanket vary significantly in the poloidal direction due to an outward shift in the deuterium-tritium neutron source distribution and the toroidal curvature. The infinite cylinder approximation overestimates response rates in the first wall compared with toroidal geometry calculations. Neutral beam lines, vacuum ducts, and other penetrations of the blanket and bulk shield represent large (∼0.6- to 1.0-m2 cross section) streaming paths for neutrons and require special shielding. A special 0.75-m-thick annular shield surrounds the neutral beam duct after it exits from the bulk shield and extends beyond the toroidal field coil and out to the beam injectors. A pneumatically operated movable shield plug, opening during the pumpdown phase and closing during the plasma burn, is selected as the principal design option for shielding the evacuation ducts.
