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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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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
The short life of the Hallam plant
The Hallam nuclear power plant in Nebraska, about 25 miles southwest of Lincoln, was a 75-MWe sodium-cooled, graphite-moderated reactor operated by Consumers Public Power District of Nebraska (CPPD). It was co-located with the Sheldon Power Station, a conventional coal-fired plant. The facility had a shared control room and featured a shared turbo generator that could accept steam from either heat source.
Pietro Mosca, Claude Mounier, Pierre Bellier, Igor Zmijarevic
Nuclear Science and Engineering | Volume 175 | Number 3 | November 2013 | Pages 266-282
Technical Paper | doi.org/10.13182/NSE12-63
Articles are hosted by Taylor and Francis Online.
This paper shows two ways to improve the accuracy of the transport calculations. These improvements, implemented in the APOLLO2 code, concern the fission source calculation and the self-shielding models. The calculation of the fission source was generalized to fission spectra including an incident neutron energy dependence. The subgroup self-shielding model was updated for a mixture of resonant nuclides. Some tests on fast neutron systems like a critical sphere without reflector, a sodium-cooled cell, and a helium-cooled cell show that the use of four optimized incident macro groups for fission spectra guarantees a correct representation of the fission source.The tests on a critical sphere with a thick steel reflector and on a water-moderated mixed oxide cell prove that the subgroup self-shielding, accounting for the mutual shielding of several resonant nuclides, allows us to improve the accuracy of the neutron transport solution.