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Division Spotlight
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.
Meeting Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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
NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
Hao Yang, Bin Zhang, Pengcheng Gao, Runze Zhai, Jianqiang Shan
Nuclear Science and Engineering | Volume 197 | Number 7 | July 2023 | Pages 1436-1453
Technical Paper | doi.org/10.1080/00295639.2022.2158676
Articles are hosted by Taylor and Francis Online.
For severe accidents, in-vessel retention (IVR) is a very effective and crucial severe accident mitigation measure. The lower head of the reactor pressure vessel plays a vital role in the IVR strategy. The failure of the lower head may lead to the release of radioactive substances into the environment. During the implementation of IVR, the lower head is in a high-temperature environment, and its main failure form is creep failure. Therefore, to ensure the successful implementation of the IVR strategy and prevent radioactive material leakage, it is necessary to conduct an in-depth analysis of the lower head. In this paper, the lower head thermal-mechanical creep failure (LHTCF) module is developed based on the theory of plate and shell and Norton-type constructive creep laws. Through the mechanical analysis of the lower head, seven failure criteria are used to evaluate the integrity of the lower head. Finally, the LHTCF module is integrated into the integrated severe accident analysis (ISAA) program, and the accuracy of the module is validated by numerical calculation of the Organisation for Economic Co-operation and Development Lower Head Failure (OLHF) experiment. Through the comprehensive judgment of different failure criteria, the final simulation results are in good agreement with the experimental data. The results show that the wall thickness at the crack decreases sharply before failure due to the effect of creep, and the stress increases abruptly at the failure time. The LHTCF module developed in this paper can accurately predict the creep behavior of the lower head, and the calculated failure time, position, and thickness distribution agree well with the experimental results.