Articles techniques et présentations

The Water management is a central issue in proton exchange membrane (PEM) Fuel Cell. The polymer electrolyte membrane required sufficient water to exhibit a high ionic conductivity. The water molecules in fuel cell operation, moves through the membrane under electro-osmotic drag, convection, diffusion etc. In order to overcome the early transport resistances, gases are humidified for enhanced performance. On the other hand, water is also generated as byproduct from the electrochemical reaction. The removal of excess water is required from electrodes and gas channels, which clogs the pores of electrode and reaction is hindered. The study of two-phase in PEMFC is vital, especially at high current densities, where liquid water affects the potential drop and performance. The process becomes, significantly complicated due to coupled flow of species, capillary action in porous media, transport of gas and liquid, phase distribution etc. The work presented here is 3D, two-phase, multispecies model for a single-channel PEMFC using the software COMSOL version 6.1. The study correlates the liquid water fraction in the channels and its effect on PEMFC performance. The investigation shows that at operating voltage of 0.6V, the current density is 1604 A/m2 and power density value of 962 W/m2 as shown in Figure 1. A higher concentration of liquid water saturation is observed at the outlet when compared with the inlet region, an indication of water removal by gas flow shown in Figure 2.