Numerical investigation of novel block flow channel on mass transport characteristics and performance of PEMFC

This study develops a three-dimensional numerical model of a proton exchange membrane (PEM) fuel cell (PEMFC) to investigate the mass transport characteristics and performance of PEMFC with novel two-block structures in the cathode channel. The results reveal that the novel two-block structures improve the efficiency of mass transport and the performance of PEMFC. Effects of the arrangement of two-block structures and the operating conditions on the PEMFC performance are investigated. It is found that the block position closer to the outlet of the channel has greater improvement of the PEMFC performance. The PEMFC performance increases firstly with the block structure number and then decreases, and the best number of block structures is 6 for the present study. The block channel has more evident effect when the PEMFC operated under high current density and small stoichiometric ratio, and the block channel is effective in a wide relative humidity (RH) range.