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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
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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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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.
Nozomu Fujimoto, Kiyonobu Yamashita, Naoki Nojiri, Mituo Takeuchi, Shingo Fujisaki, Masaaki Nakano
Nuclear Science and Engineering | Volume 150 | Number 3 | July 2005 | Pages 310-321
Technical Paper | doi.org/10.13182/NSE03-79
Articles are hosted by Taylor and Francis Online.
Annular cores were formed in start-up core physics tests of the High Temperature Engineering Test Reactor (HTTR) to obtain experimental data for verification of design codes. The first criticality, control rod (CR) positions at critical conditions, neutron flux distribution, excess reactivity, etc., were measured as representative data. These data were evaluated with the MVP Monte Carlo code, which can consider directly the heterogeneity of coated fuel particles (CFPs) distributed randomly in fuel compacts. It was made clear that the heterogeneity effect of CFPs on keff's for annular cores is smaller than that for fully loaded cores. The measured and the calculated keff's agreed with each other with differences <1%k. The calculated neutron flux distributions agreed with the measured results. A revised method was applied for evaluation of excess reactivity to exclude the negative shadowing effect of CRs. The revised and calculated excess reactivity agreed with differences <1%k/k.