The performance curves and their related parameters including the local current density distribution for these flow-field confi gurations were analyzed to show the characteristics of each design [20, 21]. This can conduct to many effects as the membrane fl ooding or drying and cause stresses in different regions of the fuel cell. Furthermore, the infl uence of fl ow direction to performance and its distribution were also reported. The prediction revealed that for stationary condition, narrower channel with wider rib spacing gives a higher performance. But, the opposite results were obtained when automotive condition has been applied