http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
리튬이온 전지의 내압변화 원인과 안전변의 작동압 피로 시험
김용삼(Yongsam Kim),엄석기(Sukkee Um) 한국자동차공학회 2012 한국자동차공학회 부문종합 학술대회 Vol.2012 No.5
Inner pressure of Li-ion battery is easily changed by temperature, battery SOC %, storage time and side reaction. Gas evolution by side reaction is main factor for inner pressure increase but the mechanism was not clearly defined. So inner pressure of Li-ion battery was directly measured during cycling and storage. Through this measurement it was found that maximum cell inner pressure came from high temperature storage by side reaction. General Li-ion battery has a vent of safety device for gas exhausting. It was predicted that vent is very weak for repeated inner pressure change because vent material is aluminum and vent is very thin. So vent fatigue test was done for operation reliability during life. The degradation of vent operation pressure by repeated inner pressure change was fount but it was not critical to vent operation.
차량용 연료전지 스택의 안정적 반응 가스 공급을 위한 중앙 유동 분배기 형상 설계에 관한 수치적 연구
정혜미(Jung, Hye-Mi),엄석기(Um, Suk-Kee),정희석(Jeong, Hui-Seok),이성호(Lee, Seong-Ho),서정도(Seo, Jeong-Do),손영진(Son, Yeong-Jin) 한국신재생에너지학회 2008 한국신재생에너지학회 학술대회논문집 Vol.2008 No.05
In this study, two types of central flow distributor designs are presented and compared to obtain the optimal compact design which has the least flow resistance and the uniform flow distribution in a vehicular fuel cell stack. For effective and reliable prediction on the thermo-flow characteristics of the reactants flow over the entire fuel cell stack domain, open channel flow in the bipolar plates of the power generating cells were simulated by applying a simplified flow resistance model with an empirical porous concept. A number of case studies were performed to figure out an optimal configuration of a central flow distributor device in terms of the time-dependent thermo-flow behavior and load-dependent flow distribution. The results showed that the stable and load-independent thermo-flow uniformity is very design specific, which is closely associated with the design of central manifolding devices in order to achieve the enhanced volumetric power density and the reliable long-lasting operating of fuel cells.
정혜미(JUNG, Hye-Mi),엄석기(UM, Sukkee),박정선(PARK, Jungsun),이원용(LEE, Won-Yong),김창수(KIM, Chang-Soo) 한국신재생에너지학회 2005 한국신재생에너지학회 학술대회논문집 Vol.2005 No.06
The effects of internal manifold designs the reactant feed-stream in Polymer Electrolyte Fuel Cells (PEFCs) is studied to figure out mass flow-distribution patterns over an entire fuel cell stack domain. Reactants flows are modeled either laminar or turbulent depending on regions and the open channels in the bipolar plates are simulated by porous media where permeability should be pre-determined for computational analysis. In this work, numerical models for reactant feed-stream in the PEFC manifolds are classified into two major flow patterns: Z-shape and U-shape. Several types of manifold geometries are analyzed to find the optimal manifold configurations. The effect of heat generation in PEFC on the flow distribution is also investigated applying a simplified heat transfer model in the stack level (i.e. multi-cell electrochemical power-generation unit). This modeling technique is well suited for many large scale problems and this scheme can be used not only to account for the manifold flow pattern but also to obtain information on the optimal design and operation of a PEMC system.
고분자 전해질 연료전지 매니폴드의 열유동 특성에 관한 수치적 연구
정혜미(Jung, Hye-Mi),엄석기(Um, Sukkee),손영준(Sohn, Young-Jun),박정선(Park, Jungsun),이원용(Lee, Won-Yong),김창수(Kim, Chang-Soo) 한국신재생에너지학회 2005 신재생에너지 Vol.1 No.2
The effects of internal manifold designs on the reactants feed-stream in Polymer Electrolyte Fuel Cells [PEFCs] is studied to figure out flow and thermal distribution patterns over an entire fuel cell stack. Reactants flows are modeled either laminar of turbulent depending on regions and the open channels in the bipolar plates are simulated by porous media where permeability should be pre-deter-mined for computational analysis. In this work, numerical models for reactants feed-stream In the PEFC manifolds are classified Into two major flow patterns: Z-shape and U-shape. Several types of manifold geometries are analyzed to find the optimal manifold configurations. The effect of heat generation in PEFC on the flow distribution is also Investigated applying a simplified heat transfer model in the stack level (i.e. multi-cell electrochemical power-generation unit). This modeling technique Is well suited for many large scale problems and this scheme can be used not only to account for the manifold flow pattern but also to obtain Information on the optimal design and operation of PEFC systems.