| A detailed steady-state isothermal, multi-component, two-dimensional transport model of a proton exchange membrane fuel cell (PEMFC) has been developed. This model was coupled with flow in porous medium, charge balance, electrochemical kinetics using an analytical solution of a diffusion-reaction problem in a spherical porous agglomerate particle and water movement in the membrane. The problem is and then solved using a finite element method. The comparison between the modeling results and previously published experimental data showed very good agreement. The solution was able to show the transport of water molecules in the membrane by electro-osmotic flux, diffusive flux, and convective flux. The model also allowed us to evaluate the effects of channel width and bipolar plate shoulder dimensions, water content, porosity, and relative humidity of the inlet streams of the anode and cathode sides on the performance of a single PEMFC. It was observed that a smaller ratio of gas channel to the shoulder exhibited better performance. Also, the higher relative humidity of the anode was found to be of greater importance to performance than the humidity of the cathode. Furthermore, a higher temperature and higher porosity favor better performance of the cell. |
