KAERI Integral Effect Test Program and the ATLAS Design

The thermal-hydraulic integral effect test (IET) program is being progressed by the Korea Atomic Energy Research Institute. This paper presents an overview of the IET program; the scientific design characteristics of the IET facility; ATLAS, which is under construction; and the experimental and analytical validation works. The ATLAS facility has the following characteristics: (a) a 1/2-height, 1/288-volume, full-pressure simulation of the APR1400, (b) geometrical similarity with the APR1400, including 2 (hot legs) × 4 (cold legs) reactor coolant loops, a direct vessel injection (DVI), an integrated annular downcomer, etc., (c) incorporation of the specific design characteristics of the 1000-MW(electric) class Korean Standard Nuclear Power Plant, such as a cold-leg injection and the low-pressure injection pumps, (d) a maximum 8% of the scaled nominal core power, and (e) simulation capability of broad scenarios, including the reflood phase of the large-break loss-of-coolant accidents (LOCAs), small-break LOCA scenarios including the DVI line breaks, steam generator tube ruptures, main steam line breaks, midloop operation, etc. The scientific design of the ATLAS was accomplished rigorously from the viewpoints of both a global and local scaling based on the three-level scaling methodology of Ishii et al. The validation works showed that the scientific design of the ATLAS test facility is sound.