| Proton exchange membrane fuel cell (PEMFC) is considered as one of the mostpromising power sources, because it is highly efficient, environmentally friendly，quiet and simple to design and operate. On the one hand, electric current is producedby electrochemical reaction. On the other hand, water is produced in PEMFC. Therewill be a lot of liquid water produced in PEMFC, because PEMFC works under theboiling point of water. Water management plays a significant role in enhancingperformance of PEMFC. Successful water management requires effective removal ofliquid water produced by electrochemical reactions. Gas diffusion layer (GDL) is animportant part of PEMFC. The shape of GDL can be changed by assembly pressure,resulting in different cross sections of flow channels. That will affect liquid watertransport in flow channel. It is very important to investigate the effects of deformationof GDL on water transportation in PEMFC flow channel.In this work, the models of cathode of PEMFC with different deformations ofGDL were developed by Fluent software. Water droplet movements in flow channelswere calculated with volume-of-fluid (VOF) method. And the boundary conditionswere corrected by user-defined-function (UDF) according to the characteristics andparameters in a real PEMFC.In this work, water droplet movements in flow channels were simulated in thechannels with different deformations of GDLs, and water droplets in different placeswere also investigated. The results showed that the more serious deformation of GDL,the faster water droplet moved in the flow channel. Water droplet movement was alsoeffected by gas flow, liquid column diameter, contact angle of GDL and contact angleof flow channel wall. These factors influenced the water droplet movements moreserious, when the water droplet in the corner of GDL and flow channel wall. In somecases, water droplet moved faster in the flow channel with small deformation of GDLthan in the flow channel with large deformation of GDL. |
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