Nuclear Engineering and Technology

Korean Nuclear Society (한국원자력학회)
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Concepts of heat dissipation of a disposal canister and its computational analysis

  • Minseop Kim (Research Center for Spent Nuclear Fuel Storage and Disposal, Korea Atomic Energy Research Institute) ;
  • Minsoo Lee (Research Center for Spent Nuclear Fuel Storage and Disposal, Korea Atomic Energy Research Institute) ;
  • Jinseop Kim (Research Center for Spent Nuclear Fuel Storage and Disposal, Korea Atomic Energy Research Institute) ;
  • Seok Yoon (Research Center for Spent Nuclear Fuel Storage and Disposal, Korea Atomic Energy Research Institute)
  • Received : 2023.02.10
  • Accepted : 2023.07.27
  • Published : 2023.11.25
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Abstract

The stability of engineered barriers in high-level radioactive waste disposal systems can be influenced by the decay heat generated by the waste. This study focuses on the thermal analysis of various canister designs to effectively lower the maximum temperature of the engineered barrier. A numerical model was developed and employed to investigate the heat dissipation potential of copper rings placed across the buffer. Various canister designs incorporating copper rings were presented, and numerical analysis was performed to identify the design with the most significant temperature reduction effect. The results confirmed that the temperature of the buffer material was effectively lowered with an increase in the number of copper rings penetrating the buffer. Parametric studies were also conducted to analyze the impact of technical gaps, copper thickness, and collar height on the temperature reduction. The numerical model revealed that the presence of gaps between the components of the engineered barrier significantly increased the buffer temperature. Furthermore, the reduction in buffer temperature varied depending on the location of the gap and collar. The methods proposed in this study for reducing the buffer temperature hold promise for contributing to cost reduction in radioactive waste disposal.

Keywords

Acknowledgement

This research was supported by the Institute for Korea Spent Nuclear Fuel (iKSNF) and National Research Foundation of Korea (NRF) grant (2021M2E1A1085193), and the Nuclear Research and Development Program of the National Research Foundation of Korea (NRF) (2021M2E3A2041351) funded by the Korean government (Ministry of Science and ICT, MSIT).

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