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Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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.
Jan Bartak, Timo Haapalehto
Nuclear Technology | Volume 106 | Number 1 | April 1994 | Pages 46-59
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT94-A34949
Articles are hosted by Taylor and Francis Online.
A top-down reflooding model was developed and implemented into the French best-estimate thermalhydraulic code CATHARE2 V1.3E. A two-dimensional mesh moving along the wall with the quench front is used to resolve the heat conduction equation in the wall near the quench front. The results of the model validation and the first assessment calculations are given. The Winfrith single-tube top-down reflooding experiments were used to validate the model. The influence of wall material, pressure, mass flux, and wall temperature on the quench front velocity are correctly predicted. The REWET-II and PERICLES experiments in rod bundle geometry were used to assess the capabilities of the code to predict simultaneous bottom and topdown rewetting. Comparison of the calculated results with the RE WET II experimental data shows the ability of the new package to calculate the key features of this complex experiment. The existence and progression of two quench fronts in the core are correctly predicted. The maximum cladding temperatures are overpredicted for experiments with combined and upper plenum injection. This difference, which is attributed to a too severe countercurrent flow limit (CCFL) calculated by the code, does not exceed 150°C. With the top-down reflooding option, improved predictions of wall temperatures in the upper part of the core in the PERICLES tests with respect to the previous version of the code were obtained, since this part of the core was rewetted by top-down quenching. To realize further improvements in combined reflooding calculations, the CCFL predicting capabilities of CATHARE should be addressed first. More detailed experimental information and additional data would also be required for in-depth assessment of the models.