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Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
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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
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.
Ulrich Grundmann, Sören Kliem
Nuclear Technology | Volume 142 | Number 2 | May 2003 | Pages 146-153
Technical Paper | OECD/NRC MSLB Benchmark | doi.org/10.13182/NT03-A3380
Articles are hosted by Taylor and Francis Online.
The Organization for Economic Cooperation and Development (OECD) Main Steam Line Break (MSLB) Benchmark was defined to validate the thermal-hydraulic system codes coupled with three-dimensional (3-D) neutron kinetic codes. The reference problem is an MSLB in a pressurized water reactor at end of cycle. The analyses were performed with the 3-D core model DYN3D, the thermal-hydraulic system code ATHLET, and the coupled code DYN3D/ATHLET. The results of the DYN3D and ATHLET simulations based on the specification are compared with the results of other participants in the final OECD reports. The effect of the thermal-hydraulic nodalization of the core, i.e., the number of coolant channels, and the influence of the coolant mixing inside the pressure vessel are studied in the paper. Calculations with a reduced number of coolant channels are performed often in coupled calculations for saving computational time. Results of a 25-channel model were compared with the 177-channel calculation (1 channel per assembly). The results for global parameters like nuclear power show only small differences for the two models; however, the prediction of local parameters such as maximum fuel temperatures requires a detailed thermal-hydraulic modeling. The effect of different coolant mixing within the reactor pressure vessel is investigated. It is shown that the influence of coolant mixing mitigates the accident consequences when 3-D neutron kinetics is applied. In case of point kinetics, coolant mixing leads to an opposite effect. To profit from the 3-D core model, a realistic description of the coolant mixing in the coupled codes is a topic of further investigations.
