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Division Spotlight
Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott 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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Smarter waste strategies: Helping deliver on the promise of advanced nuclear
At COP28, held in Dubai in 2023, a clear consensus emerged: Nuclear energy must be a cornerstone of the global clean energy transition. With electricity demand projected to soar as we decarbonize not just power but also industry, transport, and heat, the case for new nuclear is compelling. More than 20 countries committed to tripling global nuclear capacity by 2050. In the United States alone, the Department of Energy forecasts that the country’s current nuclear capacity could more than triple, adding 200 GW of new nuclear to the existing 95 GW by mid-century.
K. Sathyanarayana, Donald M. Ogden
Nuclear Technology | Volume 92 | Number 2 | November 1990 | Pages 194-203
Technical Paper | Nuclear Safety | doi.org/10.13182/NT90-A34470
Articles are hosted by Taylor and Francis Online.
A modified version of the RELAP5/MOD2 thermal-hydraulic computer code is used to perform anticipated transient without scram (ATWS) calculations for the N Reactor. The ATWS calculations are performed for a spectrum of transients to determine the accident end state in support of the Level 2/3 probabilistic risk assessment. The predicted N Reactor response to a most severe, but highly unlikely accident, due to the postulated double-ended guillotine break of the cold-leg manifold combined with the failure of scram systems, is described. The calculated core melt frequency for the N Reactor due to such an event is <10−10/yr. The transient response for this event is predicted using a single-loop, eight-level core RELAP5/ MOD2 model of the N Reactor. The reactor power behavior is modeled using point-reactor kinetics. The kinetics model includes the contributions to the reactivity from the feedback effects of core void, fuel, graphite, and water temperature variations. To verify the basic response of the model, the RELAP5 analysis results for the scram transient are compared with a twodimensional neutronics code (TWIGL) calculation. The excess reactivity results for the loss-of-coolant accident, combined with simultaneous failure of scram systems, compare favorably with three-dimensional neutronics code (3DN) computations. The analysis also shows that the fuel temperatures during the transient have increased sufficiently in the top 30% of the core leading to fuel failure. The fuel temperatures are predicted assuming a constant power profile. However, the neutronics code calculations show that the normalized power varies from 100% at the core bottom to <5% at the top for 50% voided core. Therefore, the analysis provides a very conservative estimate of fuel temperatures for the transient.
