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
Thermal Hydraulics
The division provides a forum for focused technical dialogue on thermal hydraulic technology in the nuclear industry. Specifically, this will include heat transfer and fluid mechanics involved in the utilization of nuclear energy. It is intended to attract the highest quality of theoretical and experimental work to ANS, including research on basic phenomena and application to nuclear system design.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott 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!
Latest Magazine Issues
Jun 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
July 2025
Nuclear Technology
Fusion Science and Technology
Latest News
Smarter waste strategies: Helping deliver on the promise of advanced nuclear
At COP28, held in Dubai in 2023, a clear consensus emerged: Nuclear energy must be a cornerstone of the global clean energy transition. With electricity demand projected to soar as we decarbonize not just power but also industry, transport, and heat, the case for new nuclear is compelling. More than 20 countries committed to tripling global nuclear capacity by 2050. In the United States alone, the Department of Energy forecasts that the country’s current nuclear capacity could more than triple, adding 200 GW of new nuclear to the existing 95 GW by mid-century.
Michelle Pitts, Farzad Rahnema, Tom G. Williamson, Fitz Trumble
Nuclear Technology | Volume 122 | Number 1 | April 1998 | Pages 1-18
Technical Paper | Reactor Safety | doi.org/10.13182/NT98-A2847
Articles are hosted by Taylor and Francis Online.
Hundreds of criticality experiments were performed at Oak Ridge National Laboratory in the 1950s. Several sets of these experiments were used to determine the critical properties of 233U and 235U. Here, four sets are analyzed to provide benchmark descriptions for validation of computational tools used by nuclear criticality specialists. All four sets were performed in water-reflected spherical geometry and contained a highly enriched uranyl fluoride solution (93.18% 235U) with the hydrogen-to-fissile ratio of measurements ranging from 35.8 to 1272. The scope of these experiments spans the minimum values of the subcritical mass limit curve. One experiment was never reported in the open literature, and three experiments were performed at elevated temperatures. An uncertainty in the experimental keff was found by sensitivity studies on reported measurement uncertainties, inconsistencies, and omissions in experimental parameters. To be useful for all computer codes, one-dimensional benchmark configurations were determined for all sets of experiments. The descriptions can be used to find bias values for a code/cross-section package. The keff values for similar configurations can then be corrected using the bias values. The sensitivity analysis of the experiments was performed using ONEDANT with 27-group ENDF/B-IV cross sections and MCNP with continuous-energy ENDF/B-V cross-section data. The keff values for both one- and three-dimensional configurations were found using MCNP with ENDF/B-V and ENDF/B-VI cross-section data. The values for keff for the one-dimensional configuration were also found by using ONEDANT and KENO V.a with Hansen-Roach and 27-group ENDF/B-IV cross sections.