Journal of Energy Engineering (에너지공학)

The Korean Society for Energy (한국에너지학회)
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A Preliminary Experiment for Rayleigh-Benard Natural Convection for Severe Accident Condition

중대사고시 노심용융물의 Rayleigh-Benard 자연대류 예비 실험

  • Moon, Je-Young (Department of Nuclear and Energy Engineering, Institute for Nuclear Science and Technology, Jeju National University) ;
  • Chung, Bum-Jin (Department of Nuclear and Energy Engineering, Institute for Nuclear Science and Technology, Jeju National University)
  • 문제영 (제주대학교 에너지공학과) ;
  • 정범진 (제주대학교 에너지공학과)
  • Received : 2012.05.17
  • Accepted : 2012.09.10
  • Published : 2012.09.30
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Abstract

Rayleigh-Benard natural convection experiments were carried out as the preliminary experiment to simulate the natural convection of the core melt at the severe accident conditions. This work focused on the influences of plate separation distance(s), the existence of the side walls and crust geometries of upper and lower plates. Based upon the analogy concept, a cupric acid-copper sulfate electroplating system($H_2SO_4-CuSO_4$) was employed as the mass transfer system and measurements were made for $Ra_s$ ranging from $1.06{\times}10^7$ to $2.91{\times}10^{10}$. The test results measured for a single horizontal plate were in good agreement with the correlation reported by McAdams and those for two horizontal plates showed the similar trend to the existing Rayleigh-Benard heat transfer correlations developed by Dropkin and Somerscales, Globe and Dropkin. The measured heat transfer rate decreased with the increasing separation distance between the two plates and became similar to those for a single horizontal plate. Fin arrays mounted on both upper and lower plates enhanced the heat transfer rates. For all cases, the heat transfer rates measured for open side walls are higher than those for closed ones.

원자력발전소 중대사고시 노심용융물의 Rayleigh-Benard 자연대류 문제에 대한 예비실험으로 두 평판 사이의 거리, 측면벽의 유무 및 평판의 기하구조가 열전달에 미치는 영향에 대해 실험적 연구를 수행하였다. 열전달 실험을 대신하여 상사성의 원리를 이용한 황산-황산구리 수용액의 전기도금계를 물질전달계로 채택하였다. 실험은 $Ra_s$는 $1.06{\times}10^7{\sim}2.91{\times}10^{10}$의 범위에서 실험적 조건을 변화시켜가며 열전달을 측정하였다. 실험결과 단일 수평평판에서 측정한 열전달은 McAdams의 수평평판 자연대류 열전달 상관식과 일치하였고 두 평판에서 측정한 열전달은 Dropkin과 Somerscales, Globe와 Dropkin의 Rayleigh-Benard 자연대류 열전달 상관식과 매우 유사한 경향을 보였다. 두 평판 사이의 거리가 작을 경우 열전달이 높다가 거리가 증가하면 단일 수평평판에서의 자연대류 열전달과 같아졌다. 평판에 설치된 휜(Fin)은 열전달을 향상시켰다. 모든 경우에서 측면벽이 없는 경우의 열전달이 측면 벽이 있는 경우보다 항상 높았다.

Keywords

Acknowledgement

Supported by : 한국연구재단

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