Water dynamics in the flow channel of a dead-end anode polymer electrolyte membrane fuel cell

摘要

A two-dimensional model was developed to investigate the dynamic behavior of a liquid water droplet emerging from the gas diffusion layer (GDL) into the anode flow channel of a dead-end anode proton exchange membrane fuel cell (PEMFC). The volume of fluid (VOF) method was used with a porous model to account for the multiphase flow as well as porous media transport through the GDL. To mimic the purging effect on water droplet dynamics, the anode flow channel outlet was closed and opened periodically. The closing duration was varied from 15 to 20 ms, while the purging duration was set constant at 3.5 ms, over a flow time of 50 ms. It was observed that at low current density, the closing duration can be extended to over 20 ms. However, the problem of pressure build-ups was faced. The best results were found to be for the current density of 1.00 A/cm~2.