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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver 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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Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
Min Lee, Jiing-Huae Wu
Nuclear Technology | Volume 98 | Number 3 | June 1992 | Pages 289-306
Technical Paper | Nuclear Reactor Safety | doi.org/10.13182/NT92-A34660
Articles are hosted by Taylor and Francis Online.
Operators need to initiate feed-and-bleed (F&B) cooling to depressurize and cool down the reactor coolant system (RCS) of a pressurized water reactor (PWR) in the event of a loss of all feedwater. Long-term responses of the RCS and containment of a PWR in the loss-of-all-feedwater event with and without F&B cooling are analyzed with the Modular Accident Analysis Program (MAAP) computer code. Results of the MAAP analyses are compared with those from the RELAP5/MOD2 code. Results of the MAAP analyses show that the execution of F&B cooling at 48 min, as the steam generator secondary-side water level reaches a 6%-wide range, could depressurize the RCS along the coolant saturation curve with an average cooldown rate of 13 K/h. The conditions of the RCS reach the entry point of the residual heat removal system at ∼7 h. The RCS could still be depressurized if the execution of the F&B cooling operation is delayed to 70 and 100 min, i.e., ∼6 min after steam generator secondary-side dryout and 2 min after core uncovery, respectively. The average RCS cooldown rate, however, is above the limit specified in the technical specifications. Delaying execution of F&B cooling to 133 min can still depressurize the RCS. That, however, is too late to prevent the core from melting. Plant characteristics that are important for the responses of the RCS to F&B cooling are the flow capacity and the setpoints of the pressurizer power-operated relief valves, the flow rate, and the shutoff head of the high-head safety injection system. Results of the MAAP calculations need to be interpreted carefully because of the simplified nature of the MAAP code. Benchmark exercises of the MAAP input deck against the sophisticated system analysis code are essential for the validity of the MAAP results.