1310 New Challenges in Mechanics for Nuclear Plants

Serge Pascal, CEA
Pierre Verpeaux, CEA
In a context of questioning about nuclear energy, the nuclear engineering must more than ever demonstrate the relevance of its solutions to meet future energy needs. For this, one has to:
- Enhance the safety of the current installations, while maintaining their economic competitiveness,
- Design the next generation of nuclear power plants, which will ensure the sustainability of fuel resources and provide an even higher level of safety.
In the field of structural analysis, it ensues the following scientific challenges:
- To develop and generalize scale transition modeling in order to significantly improve the predictiveness of the models and mitigate the uncertainties which will ever remain on their behavior due to the complexity of the environment and loadings.
- To characterize the ultimate behavior of structures under extreme loads. This requires a better estimation of the real loads and their couplings within the structures, and to master the numerical methods to handle the damage localization and the crack propagation.
In particular, one can mention:
- Calculation of mechanical resistance and lifetime of the nuclear fuel, in particular in case of transient loadings.
- Calculation of crack propagation, in particular in welded assemblies, to demonstrate the integrity of the components and to evaluate their lifespan.
- Calculation of ultimate behavior of civil engineering structures (reactor containments, plants, storage containers) under extreme loadings.
- Demonstration sealing of the enclosures and containers.
- Multi-physic analysis, for example for welding simulation.
To take up these challenges, it is essential to develop advanced numerical methods which are validated on analytical experiments, the recourse to direct experimentation on prototypes being extremely complex and expensive in the nuclear field. The objective of this minisymposium is to review the last improvements of the numerical techniques and demonstrate their industrial applications.