Enhanced performance of large-scale proton exchange membrane electrolyzers through a novel serpentine-point combined flow field design based on “3D+1D” modeling framework

Three-dimensional (3D) simulations have been widely used to analyze the influence of flow field structures on proton exchange membrane electrolyzer (PEMEC) performance. However, full large-scale 3D simulations often suffer from high computational costs and convergence difficulties, restricting the achievable simulation scale. To this end, a “3D+1D” modeling approach is proposed here to accelerate flow field design for improving the performance of a 100 cm2 PEMEC. Firstly, the catalyst layers and membrane are simplified into one-dimensional (1D) domains due to their extremely small thickness and diffusion dominated transport along the through-plane direction, whereas the remaining regions are resolved in 3D. During simulation, the 3D domains solve the conservation equations and supply boundary scalar information to the 1D domains, which compute fluxes and return updated source terms to the 3D domains for iterative coupling. After that, multiple flow field configurations are evaluated based on this framework. As demonstrated by the results, traditional parallel, serpentine, and point flow fields exhibit limitations such as local hotspots, high pressure drop, and gas accumulation, which deteriorate the performance of the PEMEC. Consequently, novel combined flow fields are developed by integrating traditional flow field structures to alleviate these issues. At 2 V, the serpentine-point combined structure increases current density by 5.9% and reduces maximum temperature and pressure drop by 9.4 % and 51.4 % compared with the parallel design. The “3D+1D” framework reproduces the full 3D results with a maximum temperature deviation within 0.22 ∘C and a water mole fraction deviation within 0.03, while reducing computational costs by 52.39 %. This work provides an efficient modeling framework and a promising flow field design for enhancing performance of large-scale PEMECs.