Study on In-vessel Severe Accident Progression for Light Water Reactors

PhD student: Yangli Chen

Severe accident analysis attracts more attention nowadays, especially after the Fukushima accident in 2011. The severe accident could potentially cause massive radioactive release to the environment, which threatens the living habitat and human health. In order to find prevention and mitigation for severe accident, the in-vessel phenomena of core materials during the accident must be fully understood. However, the knowledge we have is still far from that.

This project is focused on the in-vessel progression of debris remelting and melt pool formation, which are of significance to the validation and verification of mitigation strategies like In-vessel Retention (IVR). Furthermore, it also provides the foundation to study the coolability of core corium after vessel breach.

The aim of this project is to develop models that could simulate the in-vessel corium behavior. It is desired to be efficient and computationally affordable. Implementation of the model will be performed with existing codes like MELCOR or COCOMO. As an outlook, the model would be validated against experiments, and used for safety analysis for a reference reactor.