The proton exchange membrane fuel cell is applicable for the power generation of various mobility systems. As the required power is enlarged, the fuel cell also requires a large capacity cooling system to reject the heat generated by electro-chemical reactions. In general, the heat rejection of high-power fuel cell is conducted by liquid water, but aerial vehicles require air cooling as they need lightweight to increase payload.
In this study, the cooling system performance of proton exchange membrane fuel cell stack for aerial vehicles are evaluated with Aspen Custom Modeler. Then the two cooling systems are compared, the conventional system and the system with evaporative heat rejection through the radiator. The evaporation water is assumed to be captured from products of electrochemical reactions. In order to predict the amount of water discharged from the fuel cell outlet, it is necessary to simulate the water permeation passing through the electrolyte membrane, so the model developed in this study includes a differential model of channel flow of the cathode and the anode. The results show that evaporative cooling significantly reduces the size of radiator and the parasitic losses of cooling system.