The course is focused on lectures and practical work sessions on the SOFIA simulator. To perform analysis of Thermal-hydraulics during an accident of reactor or safety evaluation, IRSN, the French Technical Safety Organization, uses the Code for Analysis of Thermal-hydraulics during an Accident of Reactor and Safety Evaluation (CATHARE) which is a system code for PWR safety analysis, accident management, definition of plant operating procedures and for research and development. The module will cover the following subjects: ▪ PWR Systems and Normal Reactor Operation: – Introduction of PWR Operation, – Main PWR Systems, – General Information and Sequence Leasing to the Hot Shutdown State, – Description of the CATHARE Thermal-hydraulic Code, – Basics of Core Physics, Divergence and Core Control, – Divergence and Power Increase Turbine Coupling. ▪ Design Basis Accidents for PWR: – Description of loss of coolant Accidents (LOCA), – Large break LOCA Transient (LB LOCA), – Small break LOCA Transient (SB LOCA), Fourth sequence: failure of first actions, – Description of Steam Generator Tube Rupture (SGTR accidents), – SGTR Transient, – Sixth sequence: intervention strategy, – Seventh sequence: decision-making process for assault. ▪ Other PWR Accident: – TMI and Fukushima Accidents.