Comparative study with two reduced test facilities for air-cooled RCCS scaling law

Journal Article · Sun Aug 15 00:00:00 EDT 2021 · Nuclear Engineering and Design

DOI:https://doi.org/10.1016/j.nucengdes.2021.111276· OSTI ID:1797405

Kim, Chan Soo ^[1]; Lisowski, Darius ^[2]; Bae, Yoon Yeong ^[1]; Kim, Jong Hwan ^[1]; Lee, Sung Nam ^[1]

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1. Korea Atomic Energy Research Institute, Daejeon (South Korea)
2. Argonne National Lab. (ANL), Argonne, IL (United States)

Korea Atomic Energy Research Institute (KAERI) and Argonne National Laboratory (ANL) conducted steady-state tests at constant heat flux conditions to investigate the scale effect on heat removal behavior of the air-cooled Reactor Cavity Cooling System (RCCS). Two differently scaled-down test facilities were used in this study, KAERI’s ¼ scale with 4.0-m cavity height, and ANL’s ½ scale with 6.8-m cavity height. Two scaling laws were proposed to simulate the radiation across the cavity and the buoyancy-driven duct flow in the riser, respectively. The test matrix for KAERI and ANL test facilities focused on the scaling effect of the heated riser length with constant heat flux at the PMR200 RCCS design. The test results showed that mixed convection in the riser duct is an important factor for accurately extrapolating the thermo-fluid behavior in the prototype from the test results in the scale-down facilities. The system analysis code, GAMMA+, with improved heat transfer models predicted fairly well the air-cooled RCCS test data from two facilities. GAMMA+ analysis results showed that the predicted radiation fractions on the heated plate in the scale-down test conditions were larger than those on the reactor vessel in the prototype. The scaling law for air-cooled RCCS was improved by considering the mixed convection in the riser duct and the same radiation fraction on the heated plate. The mixed convection effect was calculated by the height ratio. The same radiation fraction provided a conservative extrapolation from the scale-down test results.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: National Research Foundation (NRF) of Korea; USDOE Office of Nuclear Energy (NE), Office of Nuclear Reactor Technologies, Advanced Reactor Technologies (ART)
• Grant/Contract Number: AC02-06CH11357
• OSTI ID: 1797405
• Journal Information: Nuclear Engineering and Design, Journal Name: Nuclear Engineering and Design Vol. 380; ISSN 0029-5493
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
Air-cooled reactor cavity cooling system
GAMMA+
High temperature gas-cooled reactor
Mixed convection
Radiation
Riser duct
Scaling law