The interaction between system thermal-hydraulics and 3-D neutron kinetics is relevant for both the safety and the design and operation of existing nuclear reactors and reactor cores. Today, advanced coupled thermal-hydraulics/neutronics computer tools along with powerful computers can perform realistic best-estimate analyses of complex power plant transients. The results provide new insights into the conversatisms for the specification of relevant operational safety margins and can imply new optimisations of emergency operating procedures in existing plants. They also improve knowledge of the physical phenomena behind "old-fashioned" problems (critical issues) in light water reactor technology, and can specifically shed light on the interaction between thermal-hydraulics and neutronics that still can challenge the design and operation of nuclear power plants.
This is the second of a series of three reports. The first is devoted to the assembly and structure of the existing database related to this subject. This publications provides the state-of-the-art report on the subject. The third report summarises the results, selects the most important findings and indicates the industry position on the related subjects.