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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 Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Latest News
X-energy receives federal tax credit for TRISO fuel facility
Advanced reactor company X-energy has been awarded $148.5 million in tax credits under the Inflation Reduction Act for construction of its TRISO-X fuel fabrication facility in Oak Ridge, Tenn.
M. Andersson, D. Blanchet, H. Nylén, R. Jacqmin
Nuclear Science and Engineering | Volume 181 | Number 2 | October 2015 | Pages 204-215
Technical Paper | doi.org/10.13182/NSE14-106
Articles are hosted by Taylor and Francis Online.
Advanced fast reactor concepts, such as the CFV core (French acronym of “Coeur à Faible effet de Vide Sodium,” meaning “low sodium void effect core”), are characterized by a heterogeneous axial core arrangement, with an inner fertile zone and a sodium plenum above the fuel. Such concepts represent a strong challenge for accurate predictions of the control-rod antireactivity effects, and the surrounding local fuel pin power. Classical equivalence procedures, which were developed for axially homogeneous cores, are put to the test when applied to such axially heterogeneous cores. In this work, we investigate the influence of variations in the local neutron spectra, for different control-rod environments, with the objective of understanding the impact of spectral variations in control-rod homogenization. This was conducted by considering a simple one-dimensional model of the equivalence procedure in which a transition zone between the fuel and control rod was introduced to represent different control-rod environments. Two types of situations were studied, one corresponding to softened neutron spectrum environments, for which the impact in the homogenized control-rod cross section was found to be smaller than 5%. The second situation was with wide elastic scattering resonances in the control-rod environment, which could locally lead to differences of up to 15% in the resulting equivalent cross sections. The reactivity effect of these changes was calculated to be less than 2%. In some cases, the numerical stability of the equivalence procedure was adversely affected, mainly in high-energy groups, due to the softening of the neutron spectra.