Equalization of energy density in boiling water reactors (as exemplified by WB-50). Development and testing of WB -50 computational model on the basis of MCU-RR code

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

Chertkov, Yu B.^1 ; Disyuk, V.V.^1 ; Pimenov, E Yu^1 ; Aksenova, N.V.^1

Tomsk Polytechnic University, Lenina Avenue, 30, Tomsk

634050, Russia^1

关键词: Burn-up distribution;    Computational model;    Computational results;    Development and testing;    Maximum concentration values;    Mean square deviation;    Measurement techniques;    Root cause analysis;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/781/1/012024/pdf
DOI  :  10.1088/1742-6596/781/1/012024

来源: IOP

【 摘 要 】

Within the framework of research in possibility and prospects of power density equalization in boiling water reactors (as exemplified by WB-50) a work was undertaken to improve prior computational model of the WB-50 reactor implemented in MCU-RR software. Analysis of prior works showed that critical state calculations have deviation of calculated reactivity exceeding ±0.3 % (ΔKef/Kef) for minimum concentrations of boric acid in the reactor water and reaching 2 % for maximum concentration values. Axial coefficient of nonuniform burnup distribution reaches high values in the WB-50 reactor. Thus, the computational model needed refinement to take into account burnup inhomogeneity along the fuel assembly height. At this stage, computational results with mean square deviation of less than 0.7 % (ΔKef/Kef) and dispersion of design values of ±1 % (ΔK/K) shall be deemed acceptable. Further lowering of these parameters apparently requires root cause analysis of such large values and paying more attention to experimental measurement techniques.