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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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 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.
Halil I. Avci, Gerald L. Kulcinski
Nuclear Technology | Volume 44 | Number 3 | August 1979 | Pages 333-345
Technical Paper | Reactor | doi.org/10.13182/NT79-A32270
Articles are hosted by Taylor and Francis Online.
The placement of liquid metals (lithium, lead, and a Pb-Li eutectic Pb4Li) between the first wall and the source of neutrons has been considered as a mechanism for extending first wall lifetimes in inertial confinement fusion reactors. This scheme is called the Internal Spectral Shifter and Energy Converter (ISSEC). All three liquid metals have been shown to reduce the radiation damage in the Type 316 stainless-steel structural first wall and thus increase the first wall lifetime. On a per-unit thickness basis, a Pb4Li ISSEC is most effective, followed by lead and lithium in decreasing order. If the first wall is operating at 300°C, it is estimated that ∼50 cm of liquid lithium or liquid lead, or ∼40 cm of liquid Pb4Li zone will give enough protection to the Type 316 stainless-steel first structural wall so that it may last for 30 yr at a nominal 5 MW/m2 wall loading and 70% plant factor. If the wall is operating at 500°C, ∼85 cm of lithium, 50 cm of lead, or 40 cm of Pb4Li is needed, and at 600°C the required ISSEC thickness goes up to ∼2 m for lithium, ∼70 cm for lead, and 65 cm for Pb4Li. The lead and Pb4Li ISSECs increase the total energy multiplication in the reactor, while the lithium ISSEC keeps it about constant. It has been shown that the liquid ISSECs could produce in the first wall a primary knock-on atom spectrum, as well as a gas production to displacement damage ratio, close to that found in fast or thermal fission test reactors, thus allowing more confidence in applying data from current systems to future fusion devices. An overall conclusion of the study is that the Pb-Li eutectic ISSEC has better characteristics than both pure lead and lithium ISSECs, and for best results it should be used at thicknesses ranging from 45 to 65 cm.
