ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
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
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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!
Latest Magazine Issues
May 2024
Jan 2024
Latest Journal Issues
Nuclear Science and Engineering
June 2024
Nuclear Technology
Fusion Science and Technology
Latest News
Securing the advanced reactor fleet
Physical protection accounts for a significant portion of a nuclear power plant’s operational costs. As the U.S. moves toward smaller and safer advanced reactors, similar protection strategies could prove cost prohibitive. For tomorrow’s small modular reactors and microreactors, security costs must remain appropriate to the size of the reactor for economical operation.
J. S. Baek, A. Cuadra, L.-Y. Cheng, A. L. Hanson, N. R. Brown, D. J. Diamond
Nuclear Technology | Volume 189 | Number 1 | January 2015 | Pages 71-86
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT13-124
Articles are hosted by Taylor and Francis Online.
A program is underway to convert the current high-enriched uranium (HEU) fuel to low-enriched uranium (LEU) fuel in the 20-MW D2O-moderated research reactor (NBSR) at the National Institute of Standards and Technology. A RELAP5 model has been developed to analyze postulated accidents in the NBSR with the present HEU fuel and a proposed LEU fuel. The model includes the reactor vessel, primary pumps, shutdown pumps, various valves, heat exchangers, and average and hottest fuel elements and flow channels in the region where flow enters through an inner plenum (6 fuel elements) and a region where flow enters through an outer plenum (24 elements). The equilibrium cycle power distributions in the fuel elements were determined based on three-dimensional Monte Carlo neutron transport calculations performed with the MCNPX code. In this paper we discuss safety analyses conducted for the loss-of-flow accidents resulting from either loss of electrical power or inadvertent throttling of flow control valves at the inlets to the inner and outer plena. The analysis shows that the fuel conversion will not lead to significant changes in the safety analysis and that the calculated maximum clad temperatures, minimum critical heat flux ratios, and minimum onset of flow instability ratios assure that there is adequate margin to fuel failure.