Multiphysics are simulations using computer applications or software to couple multiple physical events in order to predict or validate the physical real-world outcome.
The nuclear industry has always prioritised the safe, reliable and economically attractive operation of nuclear power reactors. Given these priorities, the development, validation and application of predictive reliable modelling capabilities for both normal and accident conditions has evolved from the so-called best-estimate calculations to first principle high-fidelity multiphysics simulations.
Especially important are the multiphysics interactions in reactor cores. In the past, these different interactions were treated either as boundary conditions (i.e. each physics calculation was performed independently and the impact of other physics phenomena were taken into account through boundary conditions) or using very simplistic models for some of the physics phenomena. Examples for the latter are the point kinetics model implemented in system thermal-hydraulic models or one-dimensional thermal-hydraulic models implemented in neutronics core design codes.
Recently, advances in computing power and numerical methods have broadened the appeal of multiphysics simulations, in turn highlighting the need for experiments to validate these simulations.
A community of multi-physics experts was formed within the Expert Group on System Reactor Multi-physics (EGMUP), and is responsible for advancing multi-physics activities.
Under EGMUP, the NEA has undertaken activities aimed at verification and validation of multi-physics tools, and collecting the experimental data that underpins the work.
Notably, EGMUP publishes expert guidance in the domain of multi-physics, and work conducted within EGMUP has led to numerous conference and journal publications.
EGMPEBV deal with the activities associated with the certification of experimental data and benchmark models along with establishing the processes and procedures for using the data and benchmark models for validation of modelling and simulation tools and data
The expert group deals with the activities associated with the certification of experimental data and benchmark models along with establishing the processes and procedures for using the data and benchmark models for validation of modelling and simulation tools and data.
A sodium-cooled fast reactor (SFR) is a fast neutron reactor that uses molten sodium metal as a coolant. Sodium-cooled Fast Reactors (SFRs) are the most promising type of reactors to achieve Generation IV (Gen IV) nuclear reactor goals at a reasonable time scale given the accumulated experience over the years.