본 연구에서는 수평다공성 유체층에서 유발되는 자연대류에 의한 물질전달 상관식을 이론적으로 유도하고, 실험을 통하여 이론식에서 도출된 계수들을 결정하였다. 이를 위하여 실험에서는 다공성 매질에 포화된 황산구리-황산용액내의 구리이온에 대하여 전기화학적 방법을 통하여 확산 또는 자연대류에 의한 물질전달실험을 수행하였다. 한편 다공성 유체층에 대한 Forchheimer 유동식에 대하여 미세난류모델을 적용하여 물질전달상관식을 이론적으로 유도하였으며, 그 결과 부력에 의한 추진력이 커질수록 전달상관식은 Darcy-Rayleigh수의 1/2승에 비례하는 것으로 나타났다. 전기화학실험을 통해 산출된 계수들을 적용하면 다공성 매질내에서 구리이온의 자연대류 물질전달 상관식은 다음과 같다._x000D_ sh = 0.000101(Sc_p^. Ra_p)^1/2/1-9.013(Sc_p_x000D_ ^.Ra_D)^-1/10_x000D_ 본 연구의 결과는 실험치와 잘 부합되었으며, 모델식의 원형은 물질전달단계는 물론 열전달계에서도 효_x000D_ 과적으로 활용될 수 있을 것이다.

In the present study, the correlation of mass transport induced by natural convection in a horizontal porous layer has been derived theoretically. The coefficients appearing in the theoretical correlation were determined by experimental data. In the experiment, the mass transport of copper ions in CuSo₄-H₂SO₄ solution was conducted by the electrochemical technique controlling diffusion and natural convection. The theoretical correlation for mass transport in a horizontal porous layer satisfying Forchheimer''''s flow equation was based on the microturbulence model. The resulting equation was proportional to the 1/2 power of Darcy-Rayleigh number as the magnitude of buoyancy forces increases. For the electrochemical system of copper ions, the mass transport correlation induced by natural convection is proposed as_x000D_ sh = 0.000101(Sc_p^. Ra_p)^1/2/1-9.013(Sc_p_x000D_ ^.Ra_D)^-1/10_x000D_ The present correlation looks fairly reasonable by comparing experimental results, and very_x000D_ promising for the applications of its prototype into various systems involving heat transfer as well_x000D_ as mass transfer, effectively.

Mass Transport Natural Convection Copper Ions Forchheimer's Flow Equation Microturbulence Model

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