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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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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Nuclear Science and Engineering
May 2025
Nuclear Technology
Fusion Science and Technology
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.
David L. Chapin, William G. Price, Jr.
Nuclear Technology | Volume 31 | Number 1 | October 1976 | Pages 32-47
Technical Paper | Reactor | doi.org/10.13182/NT76-A31696
Articles are hosted by Taylor and Francis Online.
Since the tokamak scheme of plasma confinement provides a toroidal source of fusion neutrons,wide variations in the source distribution at the wall surface are possible. A numerical solution of the neutron streaming equation has been applied to the calculation of the flux and current as functions of wall position for a circular crosssection tokamak and two noncircular tokamaks, the Princeton Reference Design (PRD) and the University of Wisconsin UWMAK-I. The results show significant variations in the pattern of the angular flux and substantial peaking in the scalar flux and current. For example, the current peaks at 22% above nominal for the circular case, 43% for the PRD, and 12% for UWMAK-I. The nominal value, total source ÷ total area, is the commonly stated “wall load.” Effects of this magnitude cannot be ignored in future reactor designs when power densities, damage rates, etc., are evaluated.
