Liquid water transport and removal is one of the critical issues in the proton exchange membrane fuel cell (PEMFC) for achieving good performance and durability. In this study, two novel channels with different blocks are designed to study their effects on water removal using the volume of fluid (VOF) model considering the dynamic contact angle effect. It is found that compared with the conventional straight channel, both the one-block and two-block channels can promote liquid water removal. The one-block channel leads to faster water movement and removal on the gas diffusion layer (GDL) surface, but results in a much higher pressure drop. The separated two-block channel directly drags water away from the GDL surface by the capillary wicking effect of the block surface, achieving both faster water removal and smaller pressure drop. Effects of the droplet size, air velocity and static contact angle of GDL surface on water removal are investigated comprehensively in both the novel channels, as well as the conventional straight channel, with particular attention on the variations of water removal time, water coverage ratio and pressure drop.

液态水的传输和去除是质子交换膜燃料电池 (PEMFC) 中实现良好性能和耐用性的关键问题之一。在这项研究中，设计了两个具有不同块的新型通道，以使用考虑动态接触角效应的流体体积 (VOF) 模型研究它们对除水的影响。研究发现，与常规直通道相比，一挡和二挡通道均能促进液态水的去除。单块通道导致气体扩散层 (GDL) 表面上的水运动和去除速度更快，但会导致压降高得多。分离的两块通道通过块表面的毛细管芯效应直接将水从 GDL 表面拖走，从而实现更快的除水和更小的压降。