A multiscale approach to analyze the effect of radial void fraction distributions on BWR neutronic lattice parameters. (March 2021)

• Record Type: Journal Article
• Authors: Price, Dean; Kozlowski, Tomasz
• Is Part Of: Annals of nuclear energy. Volume 152(2021)
• Publication Date: 2021-03
• Subjects: Neutronics -- BFBT -- BWR -- Serpent 2 -- Void fraction -- Cross-sections -- Criticality; Nuclear energy -- Periodicals; Nuclear engineering -- Periodicals; 621.4805
• DOI: 10.1016/j.anucene.2020.107988
• Languages: English
• ISSNs: 0306-4549

Abstract

Abstract: The aim of this study is to analyze the effect of radial void fraction distribution, considered at three degrees of fidelity, on lattice k ∞ and 2-group homogenized cross sections. The novelty of this work lies in its use of experimentally-determined radial void fraction distributions which allows for fine-scale coolant density data with no predictive uncertainty and which could be prohibitively expensive to simulate over the range of operational parameters used in the experiments. The experimentally-determined radial void fraction distributions are also characterized using a statistical tool called a semi-variogram in order to determine the scale of continuity. Void fraction distributions are averaged at the lattice and subchannel level for comparison with the fine-scale model. Models averaged at the subchannel and lattice level show a difference in k ∞ about 68% of the time. Also, by comparing 2-group homogenized cross-sections, the differences between the subchannel and homogeneous cases are measurable.