A Numerical Study on the Performance of Microfluidic Fuel Cells with Different Operating Conditions

• Main Authors: Yusuf Dewantoro Herlambang, 尤瑟夫
• Other Authors: Shun-Ching Lee
• Format: Others
• Language: en_US
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/38932703612046186036

博士 === 國立高雄應用科技大學 === 機械工程系 === 105 === This study numerically investigated the effects of various factors on the performance of air-breathing direct formic acid microfluidic fuel cells (DFAMFCs). An air-breathing microfluidic fuel cells with a microchannel width of 1.5 mm, depth of 0.05 mm, and electrode spacing of 0.3 mm was used in the simulation. Formic acid at concentrations of 0.3, 0.5, and 1.0 M was mixed with 0.5 M sulfuric acid in an aqueous solution, and the mixture served as the fuel; moreover, a 0.5 M sulfuric acid stream served as the electrolyte introduced at inlet flow rates of 0.05, 0.1, and 0.5 mL/min. First, a three-dimensional MFC model was built using COMSOL Multiphysics 5.1 to simulate the fuel cell performance. Subsequently, I–V curves obtained from simulations and from published experimental data under similar operating conditions were compared to ensure the validity of the simulation. Transport phenomena were formulated with a continuity equation, momentum equation, species transport equation, and ion charge equation. Additionally, the flow through porous media in the gas diffusion layer was described using the Brinkman equation, whereas the Butler–Volmer equations was applied to obtain I–V and P–I curves. The current density distribution resulting from fuel crossover and reactant concentration on both electrodes, the effects of bubble formation included bubble blockage, transverse dimension and the distance bubble growth between two in-line bubbles on the anode surfaces was also determined in this study.