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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.
Laurent Cantrel, Elisabeth Krausmann
Nuclear Technology | Volume 144 | Number 1 | October 2003 | Pages 1-15
Technical Paper | Reactor Safety | doi.org/10.13182/NT03-A3425
Articles are hosted by Taylor and Francis Online.
Radioiodine entering the containment from the postaccident primary circuit in vapor or gaseous form, as observed in the Phebus FPT0 and FPT1 tests, has a direct impact on the source term evaluation. State-of-the-art fission-product transport codes based on the assumption of thermochemical equilibrium failed to predict this phenomenon. In this work the standard approach of assuming the instantaneous establishment of thermochemical equilibrium is questioned and it will be argued that kinetic limitations may have existed under the severe-accident boundary conditions of the FPT0 and FPT1 tests. To this end a simple monodimensional transport model was developed in an attempt at introducing kinetic aspects within the primary circuit. A number of homogeneous gas-phase reactions between selected fission products and structural materials, complemented by condensation reactions, underlies the kinetic model. In the absence of experimental data, the kinetic constants were estimated using the transition-state theory or semi-empirical methods. The kinetic model was then applied to the analysis of Phebus FPT0 and FPT1 yielding a satisfactory agreement between experimental data and model predictions.