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Albuquerque, NM|The University of New Mexico
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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.
L. Erradi, A. Santamarina, O. Litaize
Nuclear Science and Engineering | Volume 144 | Number 1 | May 2003 | Pages 47-73
Technical Paper | doi.org/10.13182/NSE144-47
Articles are hosted by Taylor and Francis Online.
The contributions of different physical phenomena to the reactivity temperature coefficient (RTC) in typical light water moderated lattices have been assessed. Using the APOLLO2 code with the CEA93 cross-section library based on JEF2.2 data, we have analyzed the main French experiments available on the RTC: the CREOLE and MISTRAL experiments. In these experiments performed in the EOLE critical facility located at CEA/Cadarache, the RTC has been measured in both UO2 and UO2-PuO2 pressurized water reactor-type lattices. Our calculations have shown that the calculation error in UO2 lattices is <1 pcm/°C, which is considered as the target accuracy for reactor design calculations. On the other hand the calculation error in mixed oxide lattices is more significant in both low- and high-temperature ranges: An average error of -2 ± 0.5 pcm/°C is observed at low temperatures, and an error of +3 ± 2 pcm/°C is obtained for temperatures >250°C. Our analysis has shown that the negative error in the low-temperature range is linked to the thermal spectrum shift effect, which is strongly dependent on the thermal shapes of the cross sections of plutonium isotopes, whereas the positive error in the high-temperature range is mainly linked to the water density effects.
