Optimization of tapered flow channels with variable cross-sections for proton exchange membrane fuel cells based on improved genetic algorithm

The geometry, shape and structure of the flow channels significantly affect the mass transfer processes and hydrogen utilization of proton exchange membrane fuel cells (PEMFCs). This study presents a three-dimensional two-phase flow model of a rectangular single-channel PEMFC. The genetic algorithm (GA) is used to redesign the inlet and outlet cross-sectional dimensions based on the conventional rectangular flow channel, thus obtaining the optimal structure of flow channels. To enhance the optimization efficiency and accuracy of the algorithm, an improved genetic algorithm (IGA) is proposed to further optimize the traditional flow channel based on three strategies of circle chaos mapping, adaptive crossover and mutation probabilities, and Cauchy-Gaussian mutation. Results show that the optimal flow channel (OFC) is tapered, with cathode and anode taper angles of 0.38° and 0.84°, respectively. The OFC increases the power density by 19.01% at an operating voltage of 0.4V, compared with the conventional flow channel. The IGA optimization model converges 33.3% faster than the GA optimization model, achieving a remarkable performance improvement. This new approach combined with optimized algorithms provides an alluring solution for the precise design of flow channels and efficient hydrogen utilization in PEMFCs.