Focusing effect of a Metallic Layer according to the Cooling Condition and Height in a Severe Accident

중대사고시 금속용융물층의 냉각 조건과 높이가 열속 집중 현상에 미치는 영향

  • Received : 2015.02.02
  • Accepted : 2015.03.12
  • Published : 2015.03.31


Focusing effect of a metallic layer in a severe accident depending on the aspect ratios and cooling conditions of top plate and side wall was investigated. Experiments were carried out for Rayleigh numbers and aspect ratio in the range of $8.49{\times}10^7{\sim}5.43{\times}10^9$, 0.135~0.541 respectively. In order to achieve high Rayleigh numbers, the heat transfer experiments were replaced by mass transfer experiments based on the heat and mass transfer analogy. A sulfuric acid-copper sulfate ($H_2SO4-CuSO_4$) electroplating system was adopted as the mass transfer system. The experimental results agreed well with the Rayleigh-Benard natural convection correlations of Dropkin and Somerscales and Globe and Dropkin. When compared with the standard Rayleigh-Benard problem, the cooling by the side wall is even higher than the top. For a shorter height, the interaction between the heated and cooled plumes increases due to decrease of the height. Thus, the heat transfer increases.


Focusing effect;Severe accident;Core melt;Analogy concept;Electroplating system


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Supported by : 한국연구재단(NRF)