Study on a 3D multi-physics coupled model for a PEM electrolyzer with an imitation water droplet ribbed column flow field

Optimizing the flow field structure to achieve uniform water and heat distribution is crucial for enhancing electrolytic efficiency and extending the service life of the proton exchange membrane (PEM) electrolyzer. Inspired by the natural phenomenon, a novel flow field structure termed the imitation water droplet ribbed column flow field (IWRFF), is innovatively designed for the bipolar plate of the PEM electrolyzer in this paper. A 3D multi-physics coupled model has been developed to simulate the fluid flow, heat transfer, and electrochemical reactions in the PEM electrolyzer. The conventional parallel flow field (PFF) and spot flow field (SPFF) are compared with three different configurations of IWRFF. Results indicate that the application of IWRFF reduces pressure drop by 13.3%. The uniformity of liquid water saturation, temperature, and current density is enhanced by 54.4%, 73.9%, and 8.2%, respectively, and polarization performance improves by 0.9%. Additionally, the aspect ratio and arrangement of the ribbed column are explored for the performance of the PEM electrolyzer. The study finds that an aspect ratio of 1.5 and the cross arrangement of ribbed columns further improve the fluid flow, heat transfer, and electrochemical reactions of the PEM electrolyzer. This study offers novel insights and empirical evidence for optimizing PEM electrolyzer design.