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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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.
Post Critical Heat Transfer Predictions Using a Modified RELAP5/MOD2 Computer Code
Nuclear Science and Engineering | Volume 103 | Number 1 | September 1989 | Pages 70-80
Technical Paper | doi.org/10.13182/NSE89-A23661
Articles are hosted by Taylor and Francis Online.
A new modified version of the RELAP5/MOD2 computer code for the analysis of the reflood phase after a hypothetical large-break loss-of-coolant accident is developed. Various rewetting correlations are examined and compared with full-length emergency core heat transfer separate-effects and system-effects test (FLECHT-SEASET) experimental reflood data. The RELAP5 prediction of vapor temperatures is low in comparison with the data. The use of a new interfacial heat transfer between droplets and steam results in a reasonable prediction of vapor superheats. A revised dispersed flow film boiling correlation, which accounts for the enhancement of steam convective cooling by droplet-induced turbulence, is incorporated in the code. Comparison of the current results with data shows significant improvement in the prediction of clad temperature time histories over previous RELAP5 calculations.
