Modeling multiphysics transport of PEMFCs with double-oval baffle cathode flow channels: A numerical study on flow, mass transfer, and electrochemical characteristics

PEMFC is a promising clean energy technology. In this study, 3D numerical simulations were conducted to assess the impact of different baffle structures in the PEMFC cathode flow channel on flow behavior, mass transfer, water management, and cell performance, with a focus on optimizing the operating parameters of the double-oval baffle channel. The results indicate that the double oval-baffle flow channel achieves an increase in convective flux and diffusive flux are increased by up to 20% and 39.5%, respectively, and the molar concentration in the GDL is raised by 7.77%. The geometric characteristics of this channel lead to a notable rise in flow velocity at the baffle locations, effectively improving the uniformity of oxygen distribution in the cathode. This study identifies the optimal operating window for the double-oval baffle flow channel as an inlet relative humidity of 50% and an inlet temperature of 333 K. • The double-elliptical baffle channel enhances convective and diffusive mass transfer efficiency. • Streamlined structure achieves uniform O2 distribution and orderly water drainage, preventing local flooding. • Inlet temperature has a greater impact on PEMFC performance than relative humidity. • Optimal operating condition for the double-elliptical baffle channel is obtained. • Non-streamlined structures increase flow resistance and water accumulation.