• 제목/요약/키워드: Nuclear engineering

검색결과 9,735건 처리시간 0.04초

Experimental and numerical assessment of helium bubble lift during natural circulation for passive molten salt fast reactor

  • Won Jun Choi;Jae Hyung Park;Juhyeong Lee;Jihun Im;Yunsik Cho;Yonghee Kim;Sung Joong Kim
    • Nuclear Engineering and Technology
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    • 제56권3호
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    • pp.1002-1012
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    • 2024

  • To remove insoluble fission products, which could possibly cause reactor instability and significantly reduce heat transfer efficiency from primary system of molten salt reactor, a helium bubbling method is employed into a passive molten salt fast reactor. In this regard, two-phase flow behavior of molten salt and helium bubbles was investigated experimentally because the helium bubbles highly affect the circulation performance of working fluid owing to an additional drag force. As the helium flow rate is controlled, the change of key thermal-hydraulic parameters was analyzed through a two-phase experiment. Simultaneously, to assess the applicability of numerical model for the analysis of two-phase flow behavior, the numerical calculation was performed using the OpenFOAM 9.0 code. The accuracy of the numerical analysis code was evaluated by comparing it with the experimental data. Generally, numerical results showed a good agreement with the experiment. However, at the high helium injection rates, the prediction capability for void fraction of helium bubbles was relatively low. This study suggests that the multiphaseEulerFoam solver in OpenFOAM code is effective for predicting the helium bubbling but there exists a room for further improvement by incorporating the appropriate drag flux model and the population balance equation.

  • https://doi.org/10.1016/j.net.2023.12.016 인용 PDF

Comparison of the DeSa Project and the Preliminary Decommissioning Plan for Shin-Kori Units 5 and 6 in Terms of Graded Approaches

  • Changju Song;Tae Young Kong;Seongjun Kim;Jinho Son;Woo Seok Choi;hwapyoung Kim;Jiung Kim;Hee Geun Kim
    • 방사선산업학회지
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    • 제17권2호
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    • pp.143-150
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    • 2023

  • A graded approach applies safety requirements differentially, depending on the risk potential. An advantage of applying a graded approach is that safety assessments can be conducted repeatedly by focusing on areas with relatively higher risk than on those with low risk when decommissioning a nuclear power plant (NPP). The International Atomic Energy Agency (IAEA) recommends applying a graded approach to decommissioning NPPs worldwide. In Korea, the definition of the graded approach requires to be clarified. This study compared the decommissioning method used in Korean NPPs with the IAEA graded approach and examined whether the graded approach can be applied to decommissioning NPPs in Korea. As a result of the comparison, the preliminary decommissioning plan for Shin-Kori Units 5 and 6 showed that the decommissioning method for Korean NPPs is similar to the five-step IAEA graded approach.

  • https://doi.org/10.23042/radin.2023.17.2.143 인용 PDF