Numerical study on electrochemical performance of PEM fuel cell with 5 channel convergent serpentine flow field for application to eco-friendly ships

Abstract

The long-term strategy proposed by the International Maritime Organization (IMO) for reducing greenhouse gas in shipping industries requires extensive research on an alternative clean energy source like Polymer Electrolyte Membrane Fuel Cell (PEMFC). Serpentine flow channels (SFC) are widely used in PEMFC, known for their wide distribution of reactants, smooth temperature distribution, and high-pressure drop to assist water removal. Despite the advantages, this type of flow channel suffers from high flow resistances due to long channel and short bends, and non-uniform reactant distribution due to mass depletion near the channels. Though this shortcoming could be partially solved by additional serpentine channels such as 5-channel serpentine instead of a single one where the channel distance becomes short and the pressure drop reduces more, the problem remains. In this simulation study, a multiphase three-dimensional model consisting of two fluidmethods as a transport model was implemented in a PEMFC with 5 5-channel SFC and two modified designs. In addition to that two modified convergent 5-channel SFCs were designed where channel widths are gradually decreasing from inlet to outlet to mitigate the shortcomings of the conventional 5-channel SFC. Among the 3 channels, the SFC with the smallest width near the outlet showed superior performances at high current density.