Transactions of the Korean Nuclear Society Virtual Autumn Meeting December 17-18 Major Outcomes of the Second Phase of OECD-ATLAS International Joint Project

Within the context of the OECD/NEA ATLAS project from April 2014 to March 2017 [1], a series of tests were performed to resolve key thermal-hydraulic safety issues related to multiple high risk failures highlighted from the Fukushima accident, by utilizing a thermal-hydraulic integral effect test (IET) facility of ATLAS (Advanced Thermal-Hydraulic Test Loop for Accident Simulation) [2] as shown in Fig. 1. Notwithstanding the distinguished achievement of the OECD/NEA ATLAS project, a general consensus between the project partners was reached to continue the second phase of project with an aim of enhancing the nuclear safety analysis technology and improving the best guidelines for accident management. In particular, the OECD/NEA ATLAS phase 2 project (hereafter, OECD-ATLAS2 project) focused on the validation of simulation models and methods for complex phenomena of high safety relevance to thermal-hydraulic transients in design basis accident (DBA) and beyond-DBA (BDBA).