Performance Investigation of Proton‐Exchange Membrane Fuel Cell with Dean Flow Channels

Abstract

Herein, a novel fuel cell flow field with 3 π/2 radian Dean flow channels and its impact on the performance of proton exchange membrane fuel cells are presented. With a multidisciplinary numerical model, flow characteristics, concentration distribution, and current density contour in the fuel cell are compared between straight and Dean flow channel cases. The unstable vortices formed in the Dean flow channels are shown to enhance mass transfer of both reactants and water. As a result, although the voltage under low current density is slightly lower than that of fuel cells with straight channels, the output performance under high current density is observably improved. It is also found that the enhancement of oxygen transport with the Dean channel is more significant at relatively small cathode stoichiometry. In addition, by reducing the gas diffusion layer porosity, the membrane is kept at high humidity, yielding an improvement in power output and stability of the fuel cell at low cathode inlet pressure operation.