Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Numerical Study on Oxygen Depletion Characteristics of Porous Cathodes in Anode-Supported Solid Oxide Fuel Cells

음극지지 고체산화물 연료전지 다공성 양극에서의 산소고갈 특성에 관한 수치해석 연구

  • Shin, Dongwoo (School of Mechanical and Aerospace Engineering, Seoul Nat'l Univ.) ;
  • Nam, Jin Hyun (School of Mechanical Engineering, Daegu Univ.) ;
  • Kim, Charn-Jung (School of Mechanical and Aerospace Engineering, Seoul Nat'l Univ.)
  • 신동우 (서울대학교 기계항공공학부) ;
  • 남진현 (대구대학교 기계공학부) ;
  • 김찬중 (서울대학교 기계항공공학부)
  • Received : 2016.09.28
  • Accepted : 2017.01.20
  • Published : 2017.04.01
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Abstract

This paper proposes an efficient two-dimensional simulation model for solid oxide fuel cells (SOFCs) based on the electrochemical effectiveness model. The effectiveness model is known to accurately predict the current generation performance of SOFC electrodes, by considering the complex reaction/transport processes that occur within thin active functional layers near the electrolyte. After validation tests, the two-dimensional simulation model was used to calculate the distribution of current density and oxygen concentration transverse to the flow channel in anode-supported SOFCs, with which the oxygen depletion characteristics were investigated in detail. In addition, simulations were also conducted to determine the minimum number of grids required in the transverse direction to efficiently obtain accurate results.

본 논문에서는 우선 전기화학 유효도 모델에 기반하여 고체산화물 연료전지의 효율적인 2차원 해석모델을 제안하였다. 전기화학 유효도 모델은 연료전지 전극내 전해질 근처의 얇은 활성기능층에서 일어나는 복잡한 반응/전달현상을 고려하여 전극의 전류생산 성능을 정확하게 예측할 수 있는 장점을 가진다. 개발된 2차원 해석모델은 신뢰성을 검증한 후 음극지지 고체산화물 연료전지의 유로 횡방향 전류밀도 및 산소농도 분포를 계산하는데 사용되었으며 이를 통해 다공성 양극에서의 산소고갈 특성을 고찰하였다. 또한 효율적이면서도 정확한 계산을 위한 유로 횡방향 최소 필요격자수에 대한 수치해석 연구도 진행하였다.

Keywords

References

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