Abstract: The differential pressure channel utilizes the pressure variation zone to create different pressures between adjacent channels, promoting convection under the reactant ridges and enhancing the oxygen concentration in the spine area of the membrane electrode. To clarify how the size of the pressure variation zone influences the performance of differential pressure flow channels, this paper investigates the effects of two key dimensional parameters (length and height) on oxygen concentration distribution, inter-channel pressure difference, and power density. The results show that compared with the length factor, the height of the pressure variation zone has a more significant impact on battery performance. Under the condition of output voltage of 0.4 V, pressure variation zone height of 0.05 mm, and length of 1.5 mm, the power density of the differential pressure flow channel is 0.364 8 W/cm 2 . This finding clarifies the dominant role of the pressure variation zone height on the performance of the differential pressure flow channel, providing a key basis for enhancing oxygen convection in the spine area of the membrane electrode assembly and improving fuel cell power density through reasonable design of the pressure variation zone dimensions.

Key words: pressure difference channel; pressure variation zone; oxygen concentration; pressure difference

摘要： 压差流道利用变压区使相邻流道间压力不同，促进反应物脊下对流，增强膜电极脊背 区域氧气浓度。为解决变压区尺寸对压差流道性能影响机制不明的问题，文章研究变压区长 度和高度两个关键尺寸参数对压差流道氧气浓度分布、相邻流道压力差和功率密度的影响规 律。结果表明：相较于长度因素，变压区高度对电池性能的影响更为显著。在输出电压为 0.4 V、变压区高度为 0.05 mm、长度为 1.5 mm 时，压差流道功率密度为 0.364 8 W/cm 2。该 研究明确了变压区高度对压差流道性能的主导作用，为通过合理设计变压区尺寸以增强膜电 极脊背区域氧气对流、提高燃料电池功率密度提供了关键依据。

关键词: 压差流道；变压区；氧气浓度；压力差