Characteristics of a composite flow field with drop-shaped gas distribution zones and a honeycomb-like staggered channel for proton exchange membrane fuel cells

Abstract

ABSTRACT On the basis of previous studies, a staggered honeycomb-like flow field with drop-shaped gas distribution zone is proposed in this paper, and the staggered honeycomb-like flow channel can make the oxygen concentration higher, and the drop-shaped gas distribution zone can improve the uniformity of reaction gas in the flow field. A three-dimensional (3D), non-isothermal two-phase numerical model is established to study the flow field performance. First, the reaction gases in the flow field are analyzed, and it is found that the proposed flow field structure can effectively improve the concentration and uniformity of reactants. Second, the volume fraction of liquid water at the (GDL)/channel (CH) interface is analyzed, and it is found that compared with the model of the symmetrical honeycomb channel without considering the gas distribution zone, the proposed model has better water removal effect at the cathode. Finally, the effects of the proposed flow field structure on the membrane properties are discussed. In addition, the temperature uniformity and liquid water removal of PEMFC are improved under the condition of reverse flow of cathode and anode reaction gases.