A review on gas purge of proton exchange membrane fuel cells: Mechanisms, experimental approaches, numerical approaches, and optimization

The purging process has implications for the commercial application of proton exchange membrane fuel cells. Transport phenomena are essential to understand purging process and provide solutions to the purging problem. In this review, experimental researches are reviewed. Analytical and numerical models and their results are also discussed. Transport phenomena associated with the purging process include phase transitions and transport. This paper focuses are also on strategies used to optimize the purge process. These strategies include component design and purge strategy control. The results show that all effective strategies for dealing with the purging problem require an understanding of the transport mechanism. It is also suggested that future designs should focus on the directional flow of liquid water. Future models of this problem should also emphasize water evaporation-condensation phase transitions and transport. More advanced experimental methods are needed to validate numerical models.