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Mathematics & Computation
Division members promote the advancement of mathematical and computational methods for solving problems arising in all disciplines encompassed by the Society. They place particular emphasis on numerical techniques for efficient computer applications to aid in the dissemination, integration, and proper use of computer codes, including preparation of computational benchmark and development of standards for computing practices, and to encourage the development on new computer codes and broaden their use.
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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
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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.
Gilles Youinou, Alfredo Vasile
Nuclear Science and Engineering | Volume 151 | Number 1 | September 2005 | Pages 25-45
Technical Paper | doi.org/10.13182/NSE05-A2526
Articles are hosted by Taylor and Francis Online.
If it becomes necessary to stabilize the Pu inventory before the advent of Gen IV fast reactors, then it must be multirecycled in thermal neutron reactors like pressurized water reactors (PWRs). However, because of the neutron physics characteristics of Pu, it is difficult to multirecycle it in mixed-oxide (MOX)-fueled PWRs. Indeed, since there are fewer and fewer fissile isotopes in Pu, it is necessary to compensate by increasing its content, causing it to quickly reach values where the void coefficient is positive (above 12% Pu). To avoid this, Pu must be used together with enriched U so that its degradation is compensated by an increase of 235U enrichment. Two possibilities of mixing Pu and enriched U in the same assembly are presented (homogeneously and heterogeneously). In the first, called MOX-UE, all the fuel rods are made of PuO2-UenrichedO2, whereas the second, called CORAIL, contains approximately one-third of standard MOX rods (PuO2-UtailO2) and two-thirds of UO2 rods. A variant of the CORAIL concept in which the MOX rods are substituted with inert matrix fuel rods (PuO2-CeO2) was also studied. These assemblies allow Pu to be multirecycled in standard PWRs, thus stabilizing the Pu inventory between 200 and 400 t heavy metal (for a nuclear electricity production of 400 TWh(electric)/yr, i.e., typical of a country such as France). The number of reactors loaded with Pu depends on the performances of each concept in terms of Pu burning, and it represents between 80% (CORAIL with the MOX rods) and 30% (MOX-UE with 12% Pu) of the total power. There is only a small difference regarding the needs in natural U between the Pu monorecycling option and the different Pu multirecycling options. Hence, it appears that saving U should not be offered as an incentive for multirecycling Pu in PWRs.