Synthesis of the inert gas behaviour models developed in INSPYRE

The goal of this deliverable is to present a synthesis of the model developments achieved during the INSPYRE Project with respect to the description of inert gas (i.e., helium and fission gases) behaviour in MOX fuel. The models presented are designed for use in fuel performance codes and are particularly suited for the simulation of fuel experiencing fast reactor conditions (higher temperatures and burn-up compared to light water reactor conditions). They allow for fast and robust numerical solution. The principles of the models presented herein are described in Deliverable D6.1, whereas the details about the inclusion in fuel performance codes will the subject of D7.2. Despite their targeted application, all the developed models are physics-based, allowing for the use of lower-length scale information either by introducing/disregarding specific mechanisms or by defining specific model parameters. The characteristic length scale at which inert gas behaviour is described by the models herein presented is the scale of the fuel grain. This is in line with the approach followed in state-of-the-art models used in fuel performance codes. The conclusion of this deliverable includes a possible roadmap for future developments to be targeted in INSPYRE and after the end of the project.