Measurement of water thickness in PEM fuel cells and analysis of gas velocity distributions

作者：Murakawa H^*; Ueda T; Sugimoto K; Asano H; Takenaka N

来源：Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment , 2011, 651(1): 290-296.

DOI：10.1016/j.nima.2010.12.046

• Polymer electrolyte fuel cell (PEFC)
• Network analysis
• Gas velocity distributions
• Water behavior
• Neutron radiography

Fuel gas (hydrogen gas) and oxidant gas (air) are supplied to a polymer electrolyte fuel cell (PEFC). Condensation may occur in the cathode side, since the air might be super-saturated by the fuel cell reactions. If condensed water exists in a gas diffusion layer (GDL) or the gas channels, it may affect the fuel cell performances because it blocks the oxygen from reaching the cathode reaction site. Thus, water management in the PEFC is important. In order to clarify water effects on performances of a PEFC, visualization and quantitative measurements of water distributions in a PEFC were carried out by means of neutron radiography. Two-dimensional water distributions were obtained, and water ejection was confirmed. It was found that the water easily accumulated in the GDL under the rib rather than under the channel at beginning of the operation. Furthermore, a network analysis of gas-velocity distribution is applied for the experimental results. It analyzes the gas-velocity distributions depending on the flow resistance, which is the pressure drop. Applying the measured data of water thickness, gas-velocity distributions were obtained in the channel and the GDL. From the calculation, air supply in the GDL dramatically decreased with increasing of water accumulation.

• 出版日期2011-9-21