Numerical Investigations of Mass Transport Improvement Techniques of Flow Channels for PEMFCs
摘要
The multi-serpentine channel provides a more uniform distribution of reactants and better mass transfer capability than the parallel channel. In addition, the multi-serpentine channel has lower pressure drop, which is helpful to the parasitic loss. Therefore, the multi-serpentine channel is more suitable for practical polymer electrolyte membrane fuel cells. However, since it makes the flow of the reactant slower, which decreases the water removal and the mass transfer capability, so the multi-serpentine channel still needs improvement. Numerous studies have been conducted to improve the mass transfer and water removal capability of the multi-serpentine channel. There are various methods to enhance the performance of the flow channel, such as increasing the flow rate, adding obstacles to the channel, or modifying the depth and shape of the channel. These methods facilitate the transport of reactants to the catalyst layer and alleviate the concentration loss by effectively enhancing reactant transport into the porous region or reducing the diffusion path. In this study, the techniques to improve the performance of the fuel cell at the 4ch-serpentine channel were assessed and compared using computational fluid dynamics by the PEMFC performance, the oxygen molar concentration, the liquid saturation, and the uniformity of the current.