[2G08-12] Fukushima Daiichi NPS Accident

[2G10] Estimation of the In-Depth Debris Status of Fukushima Unit-2 and Unit-3 with Multi-Physics Modeling

(5)Numerical Analysis of Simulant Molten Debris Spreading and Ablation on BWR Pedestal Experiments with MPS Method

*Xin Li¹, Akifumi Yamaji¹, Guangtao Duan², Masahiro Furuya¹, Hirofumi Fukai¹, Ikken Sato³, Hiroshi Madokoro³, Yuji Ohishi⁴ (1. Waseda Univ., 2. Univ. of Tokyo, 3. JAEA, 4. Osaka Univ.)

Keywords:severe accident , decommissioning of Fukushima reactors , MPS method, numerical simulation

The decommissioning of Fukushima Daiichi (1F) Nuclear Power Plants requires knowledge of the in-depth debris status within the pedestals of 1F. As part of the Nuclear Energy Science & Technology and Human Resource Development Project (2019-2021), the Moving Particle Semi-implicit (MPS) method is being developed for simulation of multi-component liquid / solid relocation with solid-liquid phase changes. The development includes improvements of the method with respect to calculation efficiency and parallelization and addition of models to treat complex phenomena, such as heat contact resistance and turbulence heat transfer models. Validation of the code with simulated experiments are also presented. This presentation will summarize the main model developments and validation of the developed code against the simulated experiments.