An experimental study on vapor transport of a hollow fiber membrane module for humidification in proton exchange membrane fuel cells

Abstract

Water management is key in the optimization of proton exchange membrane fuel cell performance and durability. Humidifiers can be used to provide water vapor to cathode air, ensuring the proper operation of proton exchange membrane fuel cells. In this study, water vapor transport characteristics of hollow fiber membrane modules were investigated in shell-tube humidifiers under isothermal conditions, using two different test jig constructions: a convection jig and a diffusion jig. The mass transfer rate of water vapor was evaluated via the impact of various operating parameters, including temperature, flow rate, pressure, and relative humidity of inlet wet air, flow arrangements, and surface area of the tube side. The result was presented by the water vapor transport rate from wet air flow to dry air flow across the hollow fiber membrane. It was found that humidification performance could be improved with higher operating temperature, flow rate, and relative humidity of inlet wet air, lower pressure, larger membrane surface area, higher convection effect, and substituting co-current with counter-current flow configuration.