Within the context of the Nuclear Energy Agency (NEA) Advanced Thermal-hydraulic Test Loop for Accident Simulation (ATLAS) project, a series of tests were performed to resolve key thermal-hydraulic safety issues related to multiple high risk failures highlighted from the Fukushima Daiichi accident, by utilising a thermal-hydraulic integral effect test (IET) facility of ATLAS. In particular, the NEA ATLAS phase 2 project (2017-2020) focused on the validation of simulation models and methods for complex phenomena of high safety relevance to thermal-hydraulic transients in a design-basis accident (DBA) and beyond-DBA (BDBA).
This report presents major findings of the NEA ATLAS-2 project.