11:15 AM - 11:30 AM
[2J07] Estimation of the In-Depth Debris Status of Fukushima Unit-2 and Unit-3 with Multi-Physics Modeling
(10)Evaluation of debris relocation and interaction with pedestal structures in Fukushima Daichi Unit-3 with MPS method
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 developed for simulation of multi-component liquid/solid relocation with solid-liquid phase changes. With the developed MPS method, we reported preliminary results of debris relocation and interaction with pedestal structures in 1F Unit-3 in 1/10-scaled geometry at the AESJ Annual Meeting (March 2021). In this study, more detailed results of different debris distributions and structure damages are presented for simulation cases with different important influential parameters, such as different debris relocation amount/frequency and convective vapor cooling conditions from the debris surface.