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Division Spotlight
Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver 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!
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Latest News
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
J. T. Mihalczo, W. T. King
Nuclear Technology | Volume 84 | Number 2 | February 1989 | Pages 205-223
Technical Paper | Techniques | doi.org/10.13182/NT88-2
Articles are hosted by Taylor and Francis Online.
The method used since 1970 for determining the subcriticality of High-Flux Isotope Reactor (HFIR) fuel elements submerged in water is to add extra reactivity-calibrated uranium fuel plates and neutron absorber strips to a fuel element in order to achieve delayed criticality when it is submerged in water. This quality assurance (QA) verification determines that a fuel element meets reactivity specifications before it is used in the reactor. The use of the 252Cf-source-driven neutron noise analysis method to measure the subcriticality of fuel elements as an alternate to the critical experiment method was investigated by performing experiments with 29 HFIR fuel elements submerged in water. Reactivity was also measured by the break frequency noise analysis method. These measurements have shown that the 252Cf-source-driven noise analysis method can be used to determine whether HFIR fuel elements are fabricated within design specification by measuring the subcritical neutron multiplication factor of the fuel element submerged in water without the need to achieve delayed criticality. These subcritical measurements can replace the existing critical experiments for QA testing of fuel elements before use in a reactor and would be a more accurate and cost-effective method with reduced personnel radiation exposure and increased nuclear criticality safety. In addition, these experiments have shown that (a) measurements can be made with the detectors outside the water reflector tank; (b) the results do not depend on the type of detector used (neutron sensitive, gammaray sensitive, or sensitive to both neutrons and gamma rays); and (c) the method can measure the reactivity of the fuel element partially submerged and has the sensitivity to determine the effects of small uranium mass changes (∼1%) in the fuel element while the element is partially flooded (approximately half submerged) and very far subcritical. Validation of this method on these fuel elements suggests a potential for broad application of the 252Cf-source-driven noise analysis for QA testing of water reactor fuel elements where it is possible to submerge the elements in water without achieving a delayed critical state.
