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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Jacques Vlassenbroeck, Anis Bousbia Salah, Andrea Bucalossi
Nuclear Technology | Volume 172 | Number 2 | November 2010 | Pages 179-188
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT09-106
Articles are hosted by Taylor and Francis Online.
This paper presents assessment results for the natural circulation interruption (NCI) phenomenon during the cooldown phase in a nuclear pressurized water reactor. This phenomenon could take place because of several circumstances, such as an asymmetric cooldown after the loss of the forced primary flow. Under NCI conditions, the homogeneous boration of the reactor coolant system (RCS) and the connection of the RCS to the residual heat removal system could be hindered. Moreover, at very low or no primary flow rates and an operating safety injection system, a pressurized thermal shock could occur in the reactor vessel due to cold fluid stratification in the loops. It is therefore important to understand the cause of loop flow stagnation and to derive accordingly the appropriate operator actions to avoid such a phenomenon.The main goal of the current study is to assess the effect of a cooldown strategy upon the single-phase NCI occurrence. For this purpose, two scenarios with asymmetric cooling between the reactor cooling loops were investigated: The first one concerns a feedwater line break combined with a loss of offsite power (LOOP), while the second one is limited to the LOOP (or any other transient leading to the loss of the forced primary flow). The analyses were carried out using the best-estimate thermal-hydraulic system code CATHARE 2/V2.5_1mod8.1, developed by Commissariat à l'Energie Atomique, Electricité de France, AREVA, and Institut de Radioprotection et de Sûreté Nucléaire. The calculation results mainly emphasize the effect of the cooldown rate and the opening strategy of the main steam atmospheric discharge valve upon the occurrence of the NCI phenomenon.