Modelling of multi-physics phenomena in fast reactor design; Safety and experimental validation

高速炉の設計と安全に関するマルチフィジックス現象のモデル化と実験検証

二ノ方 壽*; Pellegrini, M.*; 上出 英樹 ; Ricotti, M.*

Ninokata, Hisashi*; Pellegrini, M.*; Kamide, Hideki; Ricotti, M.*

高速炉の設計と安全確保に関するマルチフィジックス現象の数値モデルとシミュレーションに関する研究の現状を示す。強調すべき点は高サイクル熱疲労における構造-流動相互作用、ナトリウム-水反応現象、炉心損傷時の多相多成分熱流動を含む評価手法の実用的な検証プログラムにある。そのような手法と検証の一部を部分効果試験,総合試験を含めて示すとともに、解析誤差と不確定性に関する定量的な検証についても言及する。

The paper provides a cursory look at current approaches in numerical modeling and simulation of typical multi-physics phenomena of concern relevant to the sodium-cooled fast reactor design and safety. Emphasis is placed on the methods that are in practice and their verification and validation programs, including for those of fluid-structure thermal interactions due to thermal striping, thermodynamics of sodium-water chemical reactions, multi-component and multi-phase flows in the fuel degradation and core meltdown phases. Several of numerical simulations of these multi-physics phenomena are shown with verification and validation programs that employ not only separate-effect small-scale experiments of clean geometry but also for large-scale integral tests or mock-up experiments. The last part of this paper will be spent on discussions on more quantitative validation basis with identification of errors and/or uncertainties based on the Bayesian rule.