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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.
Koroush Shirvan, Mujid Kazimi
Nuclear Technology | Volume 184 | Number 3 | December 2013 | Pages 274-286
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-A24985
Articles are hosted by Taylor and Francis Online.
An optimization search over all design parameters yields a boiling water reactor (BWR) with high power density (BWR-HD) at a power level of 5000 MW(thermal), equivalent to a 26% uprated Advanced BWR (ABWR), the latest version of operating BWR. This results in economic benefits, estimated to be [approximately]20% capital and operation and maintenance costs and similar total fuel cycle cost per unit electricity. A safety analysis of the BWR-HD was performed and compared with that of the ABWR. It covered a range of transients, involving a decrease in reactor coolant inventory or coolant system flow rate, changes in coolant temperature along with increase in reactor pressure, and a reactivity-initiated transient. The BWR-HD's different core flow velocity, feedwater flow rate, core inlet temperature, void coefficient of reactivity, pressure drop, core fuel loading, and volume of fluid in the core resulted in very different response to transients. In general, the 1.3-m-shorter core results in faster scram times and lower total positive reactivity insertions during the transients, which improves the BWR-HD's performance compared to that of the ABWR. The core remains covered and the pressure in the reactor pressure vessel never rises above the licensing limits during any of the simulated transients. The change in minimum critical power ratio for the BWR-HD was smaller than or equal to that of the reference ABWR in all of the six simulated transients. For the loss-of-coolant-inventory accidents and severe accidents, the BWR-HD qualitative performance was judged to be acceptable and could result in an improved response with the lower fuel and zirconium loading.