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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
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2023)
February 6–9, 2023
Amelia Island, FL|Omni Amelia Island Resort
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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Nuclear Science and Engineering
February 2023
Nuclear Technology
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Latest News
Bringing 2022 ANS Standards Committee successes into the new year
By all accounts, 2022 brought many successes for the American Nuclear Society’s Standards Committee, including the initiation of five projects, reaffirmation of 11 current standards, and publication of seven new or revised standards. The entire collection of ANS current standards has been approved or reaffirmed (reapproved without change) by the American National Standards Institute (ANSI) within the past five years, keeping ANS in 100 percent compliance with ANSI’s requirement on maintaining current American National Standards. Also, the ANS standards program was reaccredited by ANSI on August 19, 2022, with the approval of a revised set of rules and procedures. ANS’s new rules and procedures take advantage of the opportunity to develop standards-related technical reports that may be registered with ANSI.
Zeyun Wu, Robert E. Williams, J. Michael Rowe, Thomas H. Newton, Sean O’Kelly
Nuclear Technology | Volume 199 | Number 1 | July 2017 | Pages 67-82
Technical Paper | doi.org/10.1080/00295450.2017.1335146
Articles are hosted by Taylor and Francis Online.
This paper presents preliminary neutronics and thermal hydraulics safety analysis results for a low-enriched uranium (LEU) fueled research reactor concept being studied at the National Institute of Standards and Technology (NIST). The main goal of this research reactor is to provide advanced sources for neutron scattering experiments with a particular emphasis given to high intensity cold neutron sources (CNSs). A tank-in-pool type reactor with an innovative horizontally split compact core was developed in order to maximize the yield of the thermal flux trap in the reflector area. The reactor concept considered a 20 MW thermal power and a 30-day operating cycle. For non-proliferation purposes, a LEU fuel (U3Si2-Al) with 19.75 wt% enrichment was used. The core performance characteristics of an equilibrium cycle with several representative burnup states—including startup and end of cycle—were obtained using the Monte Carlo–based code MCNP6. The estimated maximum perturbed thermal flux of the core is ~5.0 × 1014 n/cm2-s. The calculated brightness of the CNS demonstrates an average gain factor of ~4 compared to the current source operated at the existing NIST reactor. Sufficient reactivity control worth and shutdown margins were provided by hafnium control elements. Reactivity coefficients were evaluated to ensure negative feedback. Thermal hydraulics safety studies of the reactor were performed using the multi-channel safety analysis code PARET. Steady-state analysis shows that the peak cladding temperature and minimum critical heat flux ratio are less than design limits with sufficient safety margins. Detailed transient analyses for a couple of hypothetical design-basis accidents show that no fuel damage or cladding failure would occur with the protection of reactor scrams. All these study results suggest this new research reactor concept offers a demonstrable potential to greatly expand the cold neutron capability with a 20 MW power and certified LEU fuels.