An Efficient Unsteady Two-Phase Flow Model for Cathode Gas Channels of a Polymer Electrolyte Fuel Cell

The importance of flow field design in a Polymer Electrolyte Fuel Cell (PEFC) cannot be overemphasized. Experimental evidence suggests the presence of a significant amount of liquid water in the PEFC gas channels and a typical driving cycle in a city suggests that a vehicular PEFC engine is unlikely to reach steady state operation under these conditions. Therefore the need for an unsteady two-phase flow model is critical. The “Multiphase Mixture” (M2) model is used to develop an efficient unsteady two-phase flow model for the cathode gas channels. Liquid water evolution in cathode gas channels and its effect on the cathode pressure drop history is investigated with the help of the model. It is an efficient tool to evaluate the performance of new flow field designs as well as to test performance loss due to channel blockage. The same model could be extended to anode gas channels.