Questions relating to the space, time end energy distribution of neutrons and radiation in different media are the domain of reactor physics. Experiments and computer simulations of static and time-dependent phenomena of nuclear technology are necessary to ensure the safe design and operation of nuclear facilities. Reactor physics serves as a boundary condition and input to many different physics and analyses of safety-related events.
A community of experts has been formed within the Expert Group on Physics of Reactor Systems (EGPRS), and is responsible for advancing a wide range of steady state and transient neutronics predictions. The group provides state-of-the-art best estimate and uncertainty analysis for many types of reactor systems.
Furthermore, a longstanding community evaluating reactor physics experimental data was formed with the support of the NEA at the turn of the millenium. The IRPhE Technical Review Group evaluates reactor physics benchmarks with well-defined uncertainties, in a standarised format aimed at using legacy and current experiments to underpin reactor physics simulations. This group produces the IRPhE Handbook.
Additionally, EGPRS publishes expert guidance in the domain of reactor physics, and the work conducted within EGPRS and the IRPhE Technical Review Group has led to numerous conference and journal publications.
The goal of the Benchmark for Uncertainty Analysis in Best-Estimate Modelling for Design, Operation and Safety Analysis of Light Water Reactors (LWR-UAM) is to determine the uncertainty in light water reactor (LWR) systems and processes in all stages of calculations. It is estimated through a simulation process of ten exercises in three phases provided by the benchmarking framework.
To ensure reliable modelling of neutron physics within a state-of-the-art transient code, the neutron kinetics part of such a code should be based on the full-scale calculation of the space-time neutron kinetics equations without use of the diffusion approximation and spatial homogenisation.
Under the guidance of the Working Party on Scientific Issues and Uncertainty Analysis of Reactor Systems (WPRS), the Expert Group on Physics of Reactor Systems (EGPRS) performs specific tasks associated with reactor physics aspects of present and future nuclear power systems.
The International Handbook of Evaluated Reactor Physics Benchmark Experiments (IRPhE) contains reactor physics benchmark specifications that have been derived from experiments that were performed at various nuclear facilities around the world.
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.
The Subgroup on Uncertainty Analysis in Modelling (UAM) for Design, Operation and Safety Analysis of Sodium-cooled Fast Reactors (SFR-UAM) was formed to check the use of best-estimate codes and data.
The Working Party on Scientific Issues and Uncertainty Analysis of Reactor Systems (WPRS) studies the reactor physics, fuel performance, and radiation transport and shielding in present and future nuclear power systems.