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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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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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TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Yasuki Kowata, Nobuo Fukumura
Nuclear Science and Engineering | Volume 127 | Number 1 | September 1997 | Pages 89-103
Technical Paper | doi.org/10.13182/NSE97-A1923
Articles are hosted by Taylor and Francis Online.
Plutonium fuel could be utilized in the entire core of a heavy water-moderated, boiling light water-cooled pressure-tube-type reactor (HWR). The coolant void reactivity, however, depends on the various parameters of the lattice. It is especially significant to clarify the effect of plutonium nuclides on the void reactivity.The void reactivities in the infinite HWR lattices have been parametrically analyzed to clarify the effects of changes in the lattice parameters on the void reactivity using the WIMS-D4 code with the JENDL-3.1 nuclear data. At present, it is known that the behavior of the void reactivity can be clarified by separating the components of fuel nuclides, neutron cross sections, energy groups, and regions in the lattice cell from the global reactivity effect, using the important reaction rates.If the fuels are the same in the macroscopic absorption cross section for the 2200 m/s neutron, it has been shown that the void reactivity shifts further to a negative direction in a narrower pitch lattice and in the plutonium-fueled lattice with a higher content of 239Pu rather than in the uranium one. The effect of reducing the void reactivity to the negative by fissile plutonium is caused mainly by the presence of the resonance cross section at ~0.3 eV of 239Pu. The higher the content of 239Pu, the less the recovery of dipped neutron flux within the resonance energy width due to a decrease in the thermal neutron scattering of hydrogen with an increase in coolant void fraction, so that the decreased resonance fission rate for 239Pu contributes to the more negative direction for the void reactivity.On the other hand, resonance at ~0.3 eV for 241Pu does not have an important role for the void reactivity because its resonance cross section is smaller than that of 239Pu.
