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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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Rakesh Chawla, Dominik Rätz, Kelly A. Jordan, Gregory Perret
Nuclear Technology | Volume 183 | Number 3 | September 2013 | Pages 321-330
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-A19421
Articles are hosted by Taylor and Francis Online.
A comprehensive program of integral experiments, largely based on the measurement of reaction rate distributions, was carried out recently in the PROTEUS zero-power research reactor at the Paul Scherrer Institute in Switzerland, employing a fuel lattice resembling that of a supercritical light water reactor. The present paper reports on the analysis of a complementary set of measurements, in which the reactivity effects of removing individual pins from the unperturbed, heterogeneously moderated reference lattice were investigated.It has been found that the detailed Monte Carlo modeling of the whole reactor using MCNPX is able - as in the case of the reaction rate distributions - to reproduce the experimental results for the pin removal worths within the achievable statistical accuracy. A comparison of reduced-geometry calculations between MCNPX and the deterministic light water reactor assembly code CASMO-4E has revealed certain discrepancies. On the basis of a reactivity decomposition analysis of the differences between the codes, it has been suggested that these could be due at least partly to CASMO-4E deficiencies in calculating the effect, upon pin removal, of the extra moderation in the neighboring fuel pins.