Numerical Simulation on Gas Purge After Shutdown in Proton Exchange Membrane Fuel Cell

Abstract:

Based on water phase change and water transport phenomenon during gas purge in proton exchange membrane fuel cell (PEMFC), a onedimensional water transport model during gas purge is developed to investigate the effect of two important factors, i.e., stack temperature and gas flow rate on the purge effectiveness. The impact of hydrogen or oxygen as anode purge gas is also compared. The simulation results show that the backdiffusion from cathode to anode is significant during initial gas purge and the impact of stack temperature is much greater than flow rate. It is efficient to use oxygen as purge gas in anode.

Key words:proton exchange membrane fuel cell(PEMFC); gas purge; membrane water content