CFD-based modelling of proton exchange membrane fuel cells

Maximum current densities are predicted under the land areas as a result of the dominant influence of ohmic losses over concentration losses on the activity at the catalyst layer. A parametric analysis shows that substantially different spatial distributions can be obtained by varying the asymmetry parameter with no noticeable change in the global current density and polarization curve. Changing the conductivity radically alters the current distribution by changing the relative influence of ohmic to activation overpotentials.