Performance investigation of a novel composite channel considering tapered-3D wavy structure.

In this study, a novel composite flow channel was proposed to address issues of gas transport obstruction, poor water removal performance, high pressure drop, and low current density within the cathode flow channel of proton exchange membrane fuel cells (PEMFCs). The flow channel could optimize performance by combining a tapered design with a 3D wave structure. Based on a controlled variable method and three-dimensional (3D) multiphase computational fluid dynamics (CFD) simulations, the effects of the flow channel inlet and outlet side length ratio L D / d , amplitude A, and wavelength λ on PEMFC performance were investigated. As shown by results, appropriate decrease of L D / d , increase of A, and reduction of λ could increase convective mass transfer in the flow channel, improve the uniformity of the reaction gas distribution, and enhance the Water removal performance. Moreover, the optimal performance was achieved when L D / d = 1 / 3 , A = 0.3 mm and λ = 4 mm for PEMFC. Finally, when the cell output voltage was 0.4 V, the current density of the novel composite flow channel was up to 6.26% higher than that of the traditional 3D wave-shaped flow channel. • A novel composite channel considering a tapered-3D wavy structure is proposed. • Impact of structural parameters on PEMFC performance studied for novel channels. • Optimal parameter combination for the novel composite flow channel achieved. • The current density of the novel composite channel can increase by up to 6.26%. [ABSTRACT FROM AUTHOR]