• apollo3®
• c3po
• external loose coupling
• icoco
• multi-physics coupling
• multi-scale
• neutronics
• pwr
• thedi
• thermal-hydraulics
• triocfd

The work carried out in collaboration with CEA presents the development and implementation of a high-fidelity multi-physics simulation framework designed for advanced nuclear reactor analysis through the coupling of the new generation deterministic neutronic code APOLLO3® and the computational fluid dynamics solver, TrioCFD. The coupling is built on a modular and flexible architecture based on the ICoCo and C3PO frameworks that manage the data exchange between the solvers. The core-level thermal-hydraulic solver THEDI has been implemented in the coupling framework as a first step toward enabling core-level multi-scale simulations.

To evaluate the proposed methodology, several simulations were performed, including nominal up to perturbed scenarios. The results confirmed the framework's ability to make accurate, reliable, and high-resolution predictions of key core parameters.

In addition, this work places strong emphasis on the automation of the entire workflow to significantly reduce the barrier to future applications, making high-fidelity analyses more accessible and reproducible. Thanks to its modular architecture, the framework can be extended beyond pressurized water reactor applications by adapting or replacing individual components.