الفهرس 
IntrductionOnly 14 pages are availabe for public view
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Abstract
An experimental and theoretical study was carried out to investigate the performance of a PEMFC under various operating conditions. In the experimental study, a plate of straight open flow channels and a serpentine flow plate were used for the cathode side in two different cell configurations. Dry hydrogen was used, while cathode feeding oxygen/air relative humidity and temperature were varied. In the theoretical study a steady state computational simple model for a single straight open channel H2/O2 PEMFC was applied to predict the fuel cell performance. The cell performance was introduced in the form of polarization curves, power density vs. current density curves and reactants utilization vs. current density curves. Also, the reactants utilization and cell electric efficiency at maximum power were presented vs. oxygen relative humidity. Experimental results showed that operating conditions affect the fuel cell performance significantly. Cell performance is improved as oxidizer relative humidity is increased and its temperature is decreased. The reactants utilization was better with increasing the oxidizer relative humidity; until flooding occurrence. A comparison with using air and pure oxygen assured that using oxygen enhanced cell performance but bad oxygen utilization was achieved for the same flow rate. It was observed that the serpentine/ straight open channels cell configuration suited using air more than oxygen. A comparison between polarization curve obtained from the theoretical study and the corresponding experimental one showed a reasonable agreement. Such CFD model can be used as a tool in the development and optimization of PEMFC.