Improvement of Modeling HTGR Neutron Physics by Uncertainty Analysis with the Use of Cross-Section Covariance Information

International Conference for Young Scientists, Specialists, and Postgraduates on Nuclear Reactor Physics 2016

Boyarinov, V.F.^1 ; Grol, A.V.^1 ; Fomichenko, P.A.^1 ; Ternovykh, M Yu^2

National Research Centre, Kurchatov Institute, Kurchatov Sq. 1, Moscow

123182, Russia^1

National Research Nuclear University, MEPhI (Moscow Engineering Physics Institute), Kashirskoe highway, 31, Moscow, Russia^2

关键词: Block modeling;    Capture reaction;    Covariance information;    Cross-section uncertainties;    Design calculations;    High temperature gas-cooled reactor (HTGR);    Multiplication factor;    Neutron physics;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/781/1/012032/pdf
DOI  :  10.1088/1742-6596/781/1/012032

来源: IOP

【 摘 要 】

This work is aimed at improvement of HTGR neutron physics design calculations by application of uncertainty analysis with the use of cross-section covariance information. Methodology and codes for preparation of multigroup libraries of covariance information for individual isotopes from the basic 44-group library of SCALE-6 code system were developed. A 69-group library of covariance information in a special format for main isotopes and elements typical for high temperature gas cooled reactors (HTGR) was generated. This library can be used for estimation of uncertainties, associated with nuclear data, in analysis of HTGR neutron physics with design codes. As an example, calculations of one-group cross-section uncertainties for fission and capture reactions for main isotopes of the MHTGR-350 benchmark, as well as uncertainties of the multiplication factor (k∞) for the MHTGR-350 fuel compact cell model and fuel block model were performed. These uncertainties were estimated by the developed technology with the use of WIMS-D code and modules of SCALE-6 code system, namely, by TSUNAMI, KENO-VI and SAMS. Eight most important reactions on isotopes for MHTGR-350 benchmark were identified, namely:10B(capt),238U(n,γ), ν5,235U(n,γ),238U(el), natC(el),235U(fiss)-235U(n,γ),235U(fiss).