Uncertainty Evaluation in Nuclear Designs of Thermal Reactors

2017 Fiscal Year Final Research Report

• Project/Area Number: 26420867
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Nuclear engineering
• Research Institution: University of Fukui
• Principal Investigator: Takeda Toshikazu 福井大学, 附属国際原子力工学研究所, 特任教授 (30116058)
• Co-Investigator(Kenkyū-buntansha): 松本 英樹 福井大学, 附属国際原子力工学研究所, 客員教授 (80607276)
• Project Period (FY): 2014-04-01 – 2018-03-31
• Keywords: 軽水炉 / 実効増倍率 / 核特性の不確かさ / 多郡ミクロ断面積 / 多郡ミクロ断面積調整 / 2郡マクロ断面積 / PWR炉心

Outline of Final Research Achievements

At first a new method has been developed to calculate sensitivity coefficients of　neutronics parameters with respect to infinite dilution cross sections. Usually
in Japan the sensitivities are calculated with respect to effective cross sections.Using the new method sensitivities for various kind of cells are calculated. Compared with the conventional sensitivities, it was found that the newly calculated sensitivities differ from the conventional results up to twice in the resonant energy groups. To reduce the uncertainties a cross section adjustment was carried out using TCA-UO2 experimental data. As the result the uncertainty of k-eff for equilibrium states of PWR cores was decreased from about 0.4% to 0.2%dk. Thus it was found that the adjustment is effective to reduce uncertainties of core parameters.

Free Research Field

原子炉物理学のうち理論・計算が専門であり、高速炉・軽水炉の研究を実施している。