ICONE15-10453 Applicability of The Diffusion and Simplified P_3 Theories for BWR Pin-by-pin Core Analysis

DOI Web Site

抄録

The pin-by-pin fine mesh core calculation method is considered as a candidate of next-generation core calculation method for BWR. In this study, the diffusion and the simplified P_3 (SP_3) theories are applied to the pin-by-pin core analysis of BWR. Performances of the diffusion and the SP_3 theories for cell-homogeneous pin-by-pin fine mesh BWR core analysis are evaluated through comparison with cell-heterogeneous detailed transport calculation by the method of characteristics (MOC). In this study, two-dimensional, 2x2 multi-assemblies geometry is used to compare the prediction accuracies of the diffusion and the SP_3 theories. The 2x2 multi- assemblies geometry consists of two types of 9x9 UO_2 assembly that have two different enrichment splittings. To mitigate the cell-homogenization error, the SPH method is applied for the pin-by-pin fine mesh calculation. The SPH method is a technique that reproduces a result of heterogeneous calculation by that of homogeneous calculation. The calculation results indicated that diffusion theory shows larger discrepancy than that of SP_3 theory on pin-wise fission rates. Furthermore, the accuracy of the diffusion theory would not be sufficient for the pin-by-pin fine mesh calculation. In contrast to the diffusion theory, the SP_3 theory shows much better accuracy on pin wise fission rates. Therefore, if the SP_3 theory is applied, the accuracy of the pin-by-pin fine mesh BWR core analysis will be higher and will be sufficient for production calculation.

収録刊行物

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ