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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.
B. E. Leonard
Nuclear Technology | Volume 11 | Number 2 | June 1971 | Pages 159-174
Technical Paper | Reactor | doi.org/10.13182/NT71-A30881
Articles are hosted by Taylor and Francis Online.
The Fuchs-Nordheim model is extended to develop an approximate solution for reactor excursion analysis that includes delayed neutrons and nonadiabatic systems. Division of the time domain allows a superposition of the prompt burst power as predicted by the Fuchs-Nordheim solution and the delayed-neutron tail power. The solutions are applicable to reactor excursions of $1.00 or above up to the time the physical or nuclear dynamic properties are changed (such as by moderator expulsion or core meltdown) or when space-time effects dominate. Time-dependent relations are obtained for both reactor power and energy generated. The initial delayed-neutron-tail power is shown to be nearly independent of pulse size. Experimental time-dependent measurements of TRIGA pulses from $1.00 to $3.21 are reported and compared; peak power and energy generated to peak power are provided. Time-dependent excursion data for the HPPR and TREAT reactors are also compared with predictions of this theory. Theoretical results are provided with figures of reactor power and total energy generated for application to excursions with minimum periods from 0.002 to 1.0 sec for reactor systems with 233U, 235U, and 239Pu fuels.
