Performance study of the evolved cathode flow field via topology optimization for proton exchange membrane fuel cell

Aiming at the issues of uneven mass transfer and excessive pressure drop in conventional flow channels of proton exchange membrane fuel cells (PEMFCs), this study integrates topology optimization with a bio-inspired free evolution concept to optimize the design of the PEMFC cathode flow field. First, a three-dimensional half-cell model and a depth-averaged method-based two-dimensional surrogate model were established. The reliability of the 2D model was validated through polarization curves and grid independence verification. Subsequently, employing a density-based topology optimization strategy with oxygen average reaction rate as the objective function, the effects of Darcy penalty factor, projection parameters, volume fraction, and design domain dimensions on optimization outcomes were investigated. Results indicate that moderate parameter combinations yield structurally clear and fluidly continuous topology-optimized flow channels. At a volume fraction of 0.6, the flow field achieves an optimal balance between pressure drop and performance. Compared with traditional parallel channels, the topology-optimized channels exhibit more uniform velocity and concentration distributions, improving peak net power density by approximately 7.52% while reduces pressure drop by approximately 87.23% lower than that of the interdigitated flow field. Furthermore, the aspect ratio and area of the design domain significantly influence flow field morphology and electrochemical performance. This research demonstrates that topology optimization combined with bio-inspired principles can effectively enhance mass transfer processes and electrochemical performance in PEMFCs, providing a novel design approach for achieving high power density and stable operation. To address the issues of nonuniform mass transfer and excessive pressure drop in conventional proton exchange membrane fuel cell (PEMFC) flow fields, this study integrates topology optimization with the concept of evolution to optimize the design of the PEMFC cathode flow field. First, a two-dimensional surrogate model was established based on the depth-averaging method. Then, by defining the objective function and boundary conditions within the design domain, the system was allowed to evolve freely through iterative optimization, resulting in an optimal flow field structure. The results show that the topology-optimized flow field increases the peak net power density by 7.52% compared to the traditional parallel flow field, while reducing the pressure drop by 87.23% compared to the interdigitated flow field, providing a novel design approach for achieving high power density and stable operation. • A 2D surrogate model of topology optimization is applied to flow design. • An evolved flow field was achieved based on topology optimization. • Net power density is 7.52% higher than that of the parallel flow field. • Pressure drop is 87.23% lower than that of the interdigitated flow field. • Proposed approach offers new insights for flow field design of PEM fuel cell.