Subchannel analysis – Current practice and development for the future

Major progress in subchannel analysis development and application are reviewed in this paper with focus mainly on the computational schemes, model improvements (including spacer grid modeling, inter-subchannel exchanges, CHF correlations, and other constitutive models), and applications for different types of reactors. The modeling of wire-wrap and spacer grids are reviewed. The validations and experimental benchmarking are discussed for subchannel analysis. Also found in this paper are recent developments in direct modeling of mixing vane spacer grids, and challenges, limitations, and directions for future development of subchannel analysis.