Configuration optimization for flow field of PEM fuel cells inspired by the fluid-directed properties of the feather of the bow and arrow

This study aims to optimize the flow field structure of proton exchange membrane fuel cells to overcome the traditional conflict between mass transfer enhancement and water management. It systematically investigates the synergistic mechanisms between the structural parameters and operating modes of the bio-inspired arrow-feather-shaped serpentine channel (BIAFSSC). Initially, a comparative analysis of four types of channels reveals that the BIAFSSC exhibits a 3.12 % improvement in oxygen distribution uniformity while maintaining low pressure loss characteristics. This finding validates the role of the cross-flow effect in the sub-channels in enhancing reaction uniformity. Subsequently, by optimizing the gas flow directions at the anode and cathode, the third flow mode is identified as the optimal configuration, significantly reducing the accumulation of liquid at the cathode inlet. Further analysis of the geometric parameters of the arrow-feather-inspired (AFI) SC indicates that a bifurcation angle of 60° yields a peak current density, which is an increase of 1.36 % compared to a 40° angle. This configuration also effectively promotes the discharge of liquid water due to its high pressure drop characteristics. Additionally, when the width of the sub-channel is optimized to 0.8 mm, the maximum reduction in pressure drop reaches 10.32 %, with only a 0.21 % decrease in the oxygen uniformity index, thereby revealing the regulatory principles of flow channel design on the balance between mass transfer and energy consumption. Finally, the study elucidates the gas–liquid transport mechanisms within the AFISC and proposes a combined baffle-type flow field optimization strategy. By reducing the contact area between the rib of bipolar plate and the gas diffusion layer, and by reconstructing the geometric shape of the channels, the output voltage increases by 1.77 %, while the water saturation at the cathode inlet significantly decreases. This approach achieves a synergistic optimization of gas–liquid transport and reaction kinetics.