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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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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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
New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
Massimiliano Fratoni, Ehud Greenspan
Nuclear Science and Engineering | Volume 168 | Number 1 | May 2011 | Pages 1-22
Technical Paper | doi.org/10.13182/NSE10-38
Articles are hosted by Taylor and Francis Online.
This study investigates the neutronic characteristics of the Pebble Bed-Advanced High Temperature Reactor (PB-AHTR), which combines TRISO fuel technology and liquid salt [flibe (2LiF-Be2F)] cooling. Compared to equivalent helium-cooled cores, the flibe-cooled cores feature a significantly larger fraction of neutron loss to coolant absorption but also a reduced neutron loss to leakage. The flibe also significantly contributes to neutron slowing-down and allows an increase of the pebbles' heavy metal-to-carbon volume ratio as compared to helium-cooled cores. In order to guarantee all negative reactivity coefficients, and in particular coolant void and temperature feedbacks, the carbon-to-heavy metal atom ratio must not exceed 300 to 400, depending on the fuel kernel diameter. The maximum burnup attainable from a PB-AHTR that is fueled with 10% enriched uranium and operated in continuous refueling is ˜130 GWd/t HM; this is comparable to the maximum burnup achieved in other high-temperature reactors, either liquid salt or gas cooled. Compared to helium-cooled pebble bed reactors, the PB-AHTR pebbles can be loaded with 2.5 times more fuel, resulting in a smaller number of pebbles to fabricate and a smaller spent-fuel volume to handle per energy generated. Relative to a light water reactor, the PB-AHTR offers improved natural uranium ore utilization and reduced enrichment capacity.