Optimization of Hourglass-Shaped Flow Channel for PEMFC Based on Kriging- GA Algorithm Under High-Temperature and High-Humidity Operating Conditions

The flow channel structure of Proton Exchange Membrane Fuel Cells (PEMFC) directly affects the mass transfer of reactive gases, liquid water management, and the output performance of the cells. In this paper, by deforming the wave-shaped block, an hourglass-shaped flow channel structure (Block-H) is developed to improve mass transfer and water management capabilities. The effects of different operating temperatures and humidities on the performance of the five flow fields were analyzed via simulation. Compared with the conventional straight flow channel (Block-S), the maximum power density of Block-H is increased by 6.91%, and its performance under high-temperature and high-humidity conditions is far superior to that of the other four fuel cell structures. The throat width and flow channel height of the hourglass-shaped flow channel were optimized by combining the Kriging surrogate model with the Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) algorithm. Simulation results indicate that, compared with the conventional straight flow channel and the unoptimized Block-H, the optimized Block-H (throat width of 0.78759 mm and flow channel height of 0.42808 mm) achieves an increase in maximum power density by 24.06% and 16.04%, respectively. Meanwhile, it further enhances water drainage capacity and gas distribution uniformity. Therefore, the hourglass-shaped flow channel structure proposed in this paper provides an excellent solution for the research on PEMFC flow channels.