Pressure Drop in Micro Channel Flow with the Electrochemical Reactions in Fuel Cell

Abstract

Narrow, long micro channels in flow plates of fuel cell are required for good reactant distribution, but also increase parasitic pumping power. Therefore, it is important to try to minimize the pressure drop in the flow channels. We investigated the pressure losses in micro channels of anodes and cathodes under cold flow conditions in straight, bend and serpentine channel designs. The results show that friction factors for cold flow could be used for the design of parallel and bend channels. However, cold flow conditions do not predict the pressure drop for serpentine channels. Compared with the other channels, serpentine channels had the lowest pressure drop under reaction conditions, but the highest, pressure drop under cold flow conditions. Under reaction conditions, part of the flow in the serpentine channels bypassed the gas diffusion layer. So the effect of bypass flow should be considered for the design of serpentine flow channels