Simulation and experimental analysis of overall performance in leaf-vein-inspired channels under rib-truncated configurations

Abstract

In order to address the challenge of optimizing both pressure drop and mass transfer performance in the proton exchange membrane fuel cell flow field design, this study introduces an innovative “rib-truncated configuration (RTC)” and applies it to the leaf-vein-inspired channel. By employing three-dimensional computational fluid dynamics (CFD) simulations, the research achieves the simultaneous reduction of pressure drop and enhancement of oxygen concentration in the cathode channel while optimizing the mass transfer pathways. A comprehensive analysis combining simulation and experimental methods is conducted to systematically evaluate the impact of key parameters of the RTC. The results demonstrate that increasing the number of truncated ribs to 7 reduces the pressure drop to 505.7 Pa, increases the current density by 2.87%, and raises the output voltage by 2.27%, effectively alleviating water flooding issues. Furthermore, optimizing the truncation angle of ribs to 27° results in a 0.8% increase in net output power density, thereby achieving the lowest pressure drop and the best water distribution. The combination of an inlet/outlet dimension of 1.0 mm by 1.0 mm and four outlets leads to a 9.5% increase in average current density and an oxygen uniformity index of 0.807, although a significant increase in pressure drop is observed. Experimental tests of the single cell confirms that the relative error in current density at 333.15 K is only 4%. Additionally, CFD simulation results reveal the heterogeneous distribution of oxygen and water within the cell, providing a reliable basis for optimizing channel design.