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DOE OSTI · 1572311

PNAR Measurement Report

Tobin, Stephen Joseph·Tupasela, Topi·Dendooven, Peter·Honkamaa, Tapani
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Abstract

STUK performed an NDA inspection at the spent fuel interim storage facility at Olkiluoto NPP during 22.7-26.7.2019. The inspection was also attended by experts from US DOELANL, Helsinki Institute of Physics, Euratom and IAEA and was made possible by the operators from TVO. The inspection included fuel verification with STUK’s new PNAR instrument and IAEA’s PGET. Simultaneous measurements were made possible with a support quadropod common for both instruments. The inspection and the results of the PGET verification are described in separate memorandums. This report focuses on the results of the PNAR verification. The inspection was the very first one performed with STUK’s PNAR instrument. Thus, the main goal of the inspection from the PNAR point-of-view was to demonstrate that the PNAR method works in practice, identify possible improvements and assess if PNAR can be utilized in SNF verification. Furthermore, the measurement campaign was an initial step in exploring the fuel parameter range where PNAR could be used and an initial investigation into quantifying the uncertainties of the system.

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11 NUCLEAR FUEL CYCLE AND FUEL MATERIALSPassive Neutron Albedo Reactivity, Spent Fuel

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Tobin, Stephen Joseph, Tupasela, Topi, Dendooven, Peter, Honkamaa, Tapani. 2019-10-25. PNAR Measurement Report. https://doi.org/10.2172/1572311

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