A parametric numerical study on the performance of polymer electrolyte membrane fuel cell with intermediate-blocked interdigitated flow field designs

Flow field design is crucial for achieving higher performance in polymer electrolyte membrane fuel cells (PEMFCs). This study uses a two-phase, multi-component, and three-dimensional model to simulate the performance of PEMFCs that use interdigitated flow field design with intermediate blocks on the cathode side. A detailed parametric study is presented to investigate the effects of various geometric and operational parameters. Of the parameters studied, inlet mass flow rate, relative humidity, and rib width had the greatest impact on cell performance. The results show that increasing the cathode stoichiometric ratio resulted in higher fuel cell performance for blocked interdigitated designs compared to parallel designs. In addition, using cathode channels with higher height values resulted in lower PEMFC performance for all flow fields. Higher values of rib/channel width ratio resulted in lower cell performance due to liquid water accumulation in the rib regions. However, at higher rib/channel width ratios, the positive effect of using interdigitated flow designs was more pronounced. Moreover, at a low relative humidity of RH = 25%, a 10.4% higher performance was obtained for the interdigitated type II compared to cases with RH = 100%, due to more effective over-rib convection and higher water removal.