Development of Multi-physics High-resolution Safety Analysis Technology for Nuclear Reactor Major Components

For the multidimensional safety analysis, a component scale thermal hydraulics code for a nuclear reactor core is developed and validated. In this development, 3 dimensional thermal hydraulics models for reactor core, downcomer, and lower- and upper-plenum are implemented. In addition, two-dimensional nuclear fuel analysis code is coupled with the core thermal hydraulics code, that is applicable to DBA and DEC accident analysis. With wall condensation and hydrogen transport models, precise analysis for the passive systems of containment and severe accident resistance technology is investigated.