CONTEXT: To prevent containment overpressure and to remove the decay heat in a severe accident scenario, passive safety systems are designed to condense the steam released by the breach and to remove the heat by a natural convective thermosiphon. The condensation of steam in the presence of non-condensable gas is therefore a key phenomenon that needs to be well modelled for system design and optimisation. The objective of this internship is to develop a condensation model for EDF's in-house single-phase CFD solver code_saturne. The model should be dedicated to the application scenario of passive containment cooling systems, i.e. steam condensation on a condenser wall in the presence of non-condensable gas at relatively low temperature and pressure. The model will then need to be further validated by public and in-house experimental data. YOUR JOB: You will work physically and on a full-time basis at the EDF R&D China Centre, located in Beijing, PRC. The main tasks are: 1. Literature review of existing CFD modelling and steam condensation studies. 2. Model development, implementation and calibration (by secondary development of code_saturne programme files in C, C++ and Fortran). 3. Creation of simulation domains and application of appropriate spatial discretisation for specific validation cases (through pre-processing tools in salome). 4. Post-processing of simulation results (through Paraview, etc.) and comparison with experimental data for model validation and verification. EXPECTED PROFILE OF THE CANDIDATE: 1. University student: Ongoing Master's programme or final year of Grande École (mandatory). 2. Academic background in nuclear engineering, energy systems or fluid dynamics (mandatory). 3. Familiar with open-source software and CAE-based numerical simulation methods and tools. A good level of computer programming (C/C++, Fortran) is a plus. 4. Professional level of English (C1 or above), both written and oral (mandatory). A good level of French B2 or above