# 수직 원형관내 자연대류 물질전달실험에서 양극의 면적과 위치가 한계전류에 미치는 영향

• Kang, Kyoung-Uk (Department of Nuclear and Energy Engineering, Jeju National University) ;
• Chung, Bum-Jin (Department of Nuclear and Energy Engineering, Jeju National University)
• 강경욱 (제주대학교 에너지공학과) ;
• 정범진 (제주대학교 에너지공학과)
• Published : 2010.01.01

#### Abstract

Natural convection heat transfer rates in a vertical pipe were measured for $Gr_H$ number from 2.1x$10^6$ to 1.2x$10^9$. Using the analogy concept, heat transfer experiments were replaced by mass transfer experiments. A cupric acid - copper sulfate ($H_2SO_4-CuSO_4$) electroplating system was adopted as the mass transfer system and the mass transfer rates were measured. Comparison of the results with the existing laminar and turbulent natural convection heat transfer correlations on a vertical plate showed very good agreements except for the high $Gr_H$ case, where the boundary layer inside the vertical pipe interferes. The agreements showed the usefulness of the analogy experiment method. Using 3 different anode size and 6 different geometrical configurations, the effects of the anode size and position were explored. As expected, the anode size and position do not affect the limiting currents for most cases. These results will be used as the experimental background for the positioning and sizing of the anodes for a more complex experiment.

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