• 한국수소및신에너지학회논문집
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• 제29권6호
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• pp.620-626
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• 2018

Recently, fuel cell field is receiving much attention as an environmentally friendly energy in the world. Among the various types of fuel cells, in the case of PEMFC, ions move through the membrane in the middle of the unit cell. Therefore, proper moisture is required inside the PEMFC. In the case of membrane type humidifier, flat membrane or hollow fiber membrane is mainly used. Since various parameters can change the performance, the performance investigation has to be carried out with parameters. In this study, water transport of hollow fiber membrane was investigated in terms of principle operating conditions such as temperature and flow rate.

• 한국수소및신에너지학회논문집
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• 제32권6호
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• pp.497-505
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• 2021

Water management is essential to improve the performance of proton exchange membrane fuel cells. This study targets to understand the characteristics of water concentration in proton exchange membrane fuel cells at a dynamic load variable environment. The fuel cell model was developed to simulate nonlinear water transport in membrane by the MATLAB/Simulink^® (MathWorks, Natick, MA, USA) platform, and it calculates water content in membrane, ionic conductivity, and predicts fuel cell performance through one-dimensional analysis.

• 한국수소및신에너지학회논문집
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• 제33권4호
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• pp.353-362
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• 2022

In this study, water diffusion in proton exchange membrane fuel cell at open circuit voltage (OCV) was analyzed through experiment. First, the reliability of the micro-sensor (SHT31) was verified. It was concluded the micro-sensor has an excellent reliability at 60℃ and 70℃. After the sensor reliability test, the temperature and relative humidity measurement in bipolar-plate was conducted at OCV. To analyze water distribution and water flux, the temperature and relative humidity was converted into dew point. To the end, it was found water concentration affects water diffusion.

• 멤브레인
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• 제7권3호
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• pp.136-141
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• 1997

토양 유기물에서 생물학적 난분해성인 부식물질을 알카리에서 추출하고 산성영역에서 침전되는 성분인 부식산을 정제, 추출하였다. 부식산의 주성분인 카르복실기가 이온교환 능력을 가지고 있는 것을 이용하여 PVA와의 불균질한 이온교환막을 제조하여 생리활성 이온인 $K^+$, $Na^＋$의 이동 및 이동속도를 검토하여 보았다. 그 결과 수소이온 농도가 높을수록 이동속도는 빠르게 나타나고, 특히 $10^-1$,$10^0$영역에서 급격한 변화를 보였다. 또한 $K^+$, $Na^＋$의 농도가 증가함에 따라 그 선택성이 나타났으며, 특히 수소이온농도 $10^0$ 일때는$K^+$이 2배정도 빠르게 이동되고 있다. 따라서 이러한 생리활성 이온의 선택성 및 이동속도의 향상으로 부식산이 이온교환막의 새로운 재료로서의 그 가능성을 나타내었다.

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2002년도 추계총회 및 학술발표회
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• pp.53-53
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• 2002

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2001년도 연료전지심포지움 2001논문집
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• pp.61-64
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• 2001

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2002년도 추계학술발표회요약집
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• pp.344.2-344
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• 2002

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2003년도 추계학술발표대회 요약집
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• pp.461.2-461.2
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• 2003

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2003년도 춘계총회 및 학술발표회
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• pp.57-57
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• 2003

• 한국수소및신에너지학회논문집
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• 제22권3호
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• pp.363-371
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• 2011

In this paper, a three-dimensional hydrogen desorption model is developed to precisely study the hydrogen desorption kinetics and resultant heat and mass transport phenomena in metal hydride hydrogen storage vessels. The metal hydride hydrogen desorption model, i.e. governed by the conservation of mass, momentum, and thermal energy is first experimentally validated against the temperature evolution data measured on a cylindrical $LaNi_5$ metal hydride vessel. The equilibrium pressure used for hydrogen desorption simulations is derived as a function of H/M atomic ratio and temperature based on the experimental data in the literature. The numerical simulation results agree well with experimental data and the 3D desorption model successfully captures key experimental trends during hydrogen desorption process. Both the simulation and experiment display an initial sharp decrease in the temperature mainly caused by relatively slow heat supply rate from the vessel external wall. On the other hand, the effect of heat supply becomes influential at the latter stages, leading to smooth increase in the vessel temperature in both simulation and experiment. This numerical study provides the fundamental understanding of detailed heat and mass transfer phenomena during hydrogen desorption process and further indicates that efficient design of storage vessel and heating system is critical to achieve fast hydrogen discharging performance.