3D CFD Analysis of Flow and Thermal Dynamics of PEM Water Electrolyzer

The proton exchange membrane (PEM) water electrolyzer is an emerging technology to produce green hydrogen due to its compactness and producing high purity hydrogen. This study presents a numerical investigation on multiphase flow dynamics and heat transfer within the anode flow field of a PEM water electrolyzer. Two different channel configurations, i.e., rectangular, semi-circular are considered having same cross-sectional area while keeping the porous transport layer (PTL) thickness constant (which is within the commercially available ranges). Simulations are conducted for various oxygen generation rates and heat fluxes (corresponding to different current densities) and different inlet water flow rates. The effects of channel configurations on pressure drop, flow uniformity, and temperature distribution are illustrated pictorially and graphically. The impact of water flow rates and oxygen generation rates on phase distribution, pressure drop, and temperature profiles, particularly focusing on hot spot regions and oxygen starvation regions are investigated thoroughly. Detailed oxygen concentration distributions and temperature contours at various locations are depicted for different geometrical and operating condition that are crucial for effective functioning of the membrane. This study brings out the importance of channel configurations, operating current densities on PEM water electrolyzer performance. The insights gained are expected to guide the design of new anode plates, aiming to mitigate issues such as hot spots and oxygen starvation, ultimately leading to improved efficiency and reliability of PEM water electrolyzer in sustainable hydrogen production.