Özet:

In this investigation, a three dimensional, single-phase proton exchange membrane (PEM) fuel cells with triple-serpentine flow channel was studied numerically, evaluating reactant gas humidification, water management and cell performance. The model equations were solved using CFD software ANSYS Fluent® 16.2 with Gambit® (2.4.6) as a pre-processor. This 3-D model with 19x50 mm2 active layer used to investigate the performance of fuel cell by determining the current density, oxygen, hydrogen and water molar concentration distributions took into account the mass, momentum, energy, species, charge conservation equation as well as combines electrochemistry reaction inside the fuel cell. The simulation results were illustrated polarization curves including I–V and I–P curves. Various properties of the GDL such as permeability, porosity, tortuosity and the hydrophobic texture can affect the flooding at flow channels. In this study, the effect of GDL porosity on flooding was investigated with different operating conditions. From the results, for lower operating voltages, as the cathode and anode relative humidity increases, the cell performance is enhanced because the cell performance is mainly dependent on the cathode mass transport limitations due to the liquid water blockage effect. As decreases, the oxygen concentration in the reactants increases and the water concentration on the cathode side decreases, this reduces flooding and improves the cell performance. Also, analysing the polarization curve it can be said the performance of the PEM fuel cell was improved by increasing the reactant gases humidification.

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