Oecd-nea expert group on multi-physics experimental data, benchmarks and validation

Coupled multi-physics computational methods continue to evolve to meet the needs of the R&D community designers, operators and safety regulators, in order to improve predictive accuracy and precision and to evaluate complex operational or accidental scenarios. Novel multi-physics simulation tools are designed to enable rigorous modelling of coupled behaviors between, inter alia, reactor physics, thermal-hydraulics, fuel performance and coolant chemistry. In order to be used to their full potential, these tools will require a more complex array of validation tests due to the multiple length and time scales, as well as the number of physical phenomena being simulated. However, the ability to conduct appropriate validation experiments has either progressed very little or in some cases significantly regressed. Recognition of this divide has led research and industry experts from across the NEA nuclear science community to form a new Expert Group on Multi-physics Experimental Data, Benchmarks and Validation (EGMPEBV). The paper describes the over-arching objectives of the group, in relation to the original motivations and eventual output goals. The specific tasks to be completed under the direction of the two established Task Forces are then presented alongside a depiction their inter-dependence.