Parametric estimation of heat and water management strategy preventing condensed water formation in polymer electrolyte fuel cells

Abstract

This work presents the comprehensive theoretical and numerical modeling efforts on the water transport phenomena in polymer electrolyte fuel cells and intends to elucidate an optimal water management strategy preventing condensed water formation in the anode and cathode channels. For a particular design of polymer electrolyte fuel cells, theoretical and numerical analyses on the inlet feed streams were conducted to set an optimal water transport strategy. The results showed that the favorable water transport scenario (half of produced water transported back to anode) requires less humidification at the gas channel inlets compared to the worst scenario (10% of the produced water diffused back to anode). It was also shown that for 80°C operation of fuel cells, the reactants should be super-saturated and the coolant temperature difference less than 5°C between the inlet and outlet has a significant effect on the humidification of reactant gases. For an optimal system, the inlet feed stream temperature and the temperature difference of the coolant should be carefully determined, considering the humidification capacity and the size of the radiator.