The design of the flow field structure for bipolar plates significantly influences the output performance of proton exchange membrane fuel cells (PEMFCs). Adding baffles in the flow channels can enhance the transportation of reactants and electrochemical performance of the PEMFCs. In this study, three types of baffles with different shapes and sizes were designed. Computational fluid dynamics (CFD) models for the PEMFCs with a symmetrical serpentine flow field (SSFF), both without baffles and with baffles, were established using the CFD method. Numerical simulations for the PEMFCs, both without baffles and with baffles, were performed by FLUENT software. The simulation results show that the PEMFCs with baffles demonstrated improved oxygen transport and increased reaction gas concentrations in the flow channels compared to the PEMFCs without baffles. The velocity magnitude exhibited abrupt changes as the fluid passed through the baffles due to their disturbance effect. Specially, the PEMFCs without baffles had a maximum power density of 0.601 W/cm2, while the PEMFCs with rectangular baffles reached a maximum power density of 0.755 W/cm2, which was enhanced by 25.6% due to the arrangement of baffles in the symmetrical serpentine flow channels.
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