Abstract
The optimal structure of the gas diffusion layers (GDL) with the linear wettability pattern perpendicular to the rib in a polymer electrolyte fuel cell (PEFC) was investigated to improve the water discharge characteristic from the GDL under rib. The wettability and the width of the pattern were focused on and the suitable design was investigated by the lattice Boltzmann method (LBM). The result showed that the water discharge is the most efficient when the hydrophobic pattern was applied with the super hydrophobic GDL. The water discharge characteristic of the GDL with the hydrophilic pattern was worse because the water was wicked into the pores in the pattern and the water was not discharged from the pattern. The simulation result also clarified that it is necessary to make the width larger than the pore diameter of the GDL to control the water transport in the GDL.