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.
Harold E. Clark, Grover Tuck
Nuclear Technology | Volume 13 | Number 3 | March 1972 | Pages 257-263
Technical Paper | Chemical Processing | doi.org/10.13182/NT72-A31080
Articles are hosted by Taylor and Francis Online.
An empirical formula has been developed for the criticality specialist who does not have readily available a computer that calculates the individual cylinder diameter for a critical uranyl nitrate solution slab-cylinder system. The formula is used to calculate the criticality condition for an accidental leak in an array of fissile-containing vessels which forms a solution slab under the array. The critical system consisted of a square array of 1, 4, 9, or 16 vertical, equal-diameter cylinders resting on and interacting with a horizontal slab. Both the array and the slab were filled with ∼495 g U/liter uranyl nitrate solution with the uranium enriched to 93.2 wt% 235U. The empirical formula, which predicts the critical unit cylinder diameter of the slab-array system, is where Da is the critical unit cylinder diameter of the array alone at 500 g U/ liter. The independent variables are the number of cylinders, N; the edge-to-edge spacing between nearest neighbored cylinders in cm, S; the array solution height in cm, H; the solution concentration in g U/liter, C; and the solution slab thickness in cm, T. The calculated unit cylinder diameter, Ds, in cm, is within ±11% of the experimentally measured diameter for 65 critical slab-array systems. This accuracy is sufficient for calculating the accident condition for nuclear safety purposes. Monte Carlo calculations were performed on some typical experimental configurations. The average keff ranges from 0.977 ± 0.017 to 0.996 ± 0.012. By increasing the slab thickness by the experimental error, the low keff was increased to 0.998 ± 0.012.
