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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
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!
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Latest News
ANS Standards Committee publishes joint ASME/ANS standard for Level 1/large early release frequency PRA
ANSI/ASME/ANS RA-S-1.1-2024, Standard for Level 1/Large Early Release Frequency Probabilistic Risk Assessment for Nuclear Power Plant Applications, has been published by the American Nuclear Society. The document, which is a joint standard developed with the American Society of Mechanical Engineers by the ANS/ASME Joint Committee on Nuclear Risk Management, received the approval of the American National Standards Institute on February 29, 2024, and was issued on March 15, 2024.
Chenghui Wan, Wenchang Dong, Lin Guo, Jiahe Bai
Nuclear Science and Engineering | Volume 197 | Number 7 | July 2023 | Pages 1454-1466
Technical Paper | doi.org/10.1080/00295639.2022.2158704
Articles are hosted by Taylor and Francis Online.
The “two-step” scheme based on assembly homogenization is widely applied in simulations for pressurized water reactor (PWR) cores in which the few-group constants of the fuel assembly are generated with the single-assembly simulation. However, the reflective boundary condition adopted in the single-assembly simulation can’t characterize the real environment in the core, especially the strong heterogeneity between the neighboring assemblies. In order to consider the environmental effects on the homogenized few-group constants, a rehomogenization method is proposed. In this method, the heterogeneous neutron spectral of single-assembly model of the reflective boundary condition is corrected with the homogeneous neutron spectral of the real core environment. Through definition and precalculation of the rehomogenization factors for few-group constants during the fuel assembly simulation, corresponding corrected constants can be recomputed during the core simulation to consider the environmental effects. This method has been implemented in our home-developed code Bamboo-C. For method verification, both the heavy reflector PWR EPR1750 and the baffle reflector PWR HPR1000 have been simulated. It can be observed that the biases of the eigenvalues can be notably reduced with the proposed rehomogenization method. The assembly-averaged powers of the peripheral fuel assemblies were also notably reduced, especially for the EPR1750, which indicates that the environmental effects can be appropriately solved with the rehomogenization method.