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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
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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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.
Mark S. Jarzemba
Nuclear Technology | Volume 124 | Number 1 | October 1998 | Pages 82-87
Technical Paper | Reprocessing | doi.org/10.13182/NT98-A2910
Articles are hosted by Taylor and Francis Online.
A method is described to estimate the heat generation rate of various high-level waste (HLW) forms composed primarily of either a sludge (with a composition similar to that in the Hanford HLW tanks) or borosilicate glass. The main heat source is from radioactive decay and subsequent self-absorption of particles emitted from 137Cs, 90Sr, or their radioactive daughters contained in the waste form. The heat generation rate of the waste form is usually an important parameter in safety and performance assessments and will likely be a part of the specifications required for the vitrified waste. The heat generation rate depends on the size of the waste because larger waste forms will tend to absorb a greater fraction of the gamma radiation from 137mBa decays (a short-lived radioactive daughter of 137Cs). Because beta radiation from these two nuclides is short ranged (only a few tenths of a millimetre in water), assumption of complete self-absorption of beta radiation is justifiable. Previous work in this area estimated upper and lower bounds for the volume-averaged heat generation rate per litre of waste based on total (i.e., large-sized waste forms) and zero (i.e., small-sized waste forms) self-absorption of gamma radiation emitted from 137mBa. This analysis extends the previous work to more adequately estimate the heat generation rate of intermediate-sized waste forms based on the composition of the waste (either borosilicate glass or a simulated sludge), and the size of the waste as characterized by the surface-area-to-volume ratio. The analyses are based on runs of the MCNP version 4A code.