Effect of humidification on distribution and uniformity of reactants and water content in PEMFC

Abstract Restricted by experimental conditions, it is difficult to analyze reactants distribution and uniformity through experiment. A simulation model is established by experiment fuel cell. Hydrogen humidification has a great impact on hydrogen distribution and concentrates in inlet and serpentine sections. At anode side membrane water content increases significantly when hydrogen relative humidity is over 50%. Air humidification has little effect on air distribution and water content. The oxygen mass fraction only decreases with relative humidity increase. Hydrogen humidification has greater influence on the distribution of reactants and membrane water content than air humidification, but hydrogen humidification needs to control the relative humidity of hydrogen within a suitable range. According to the simulation results in this article, the relative humidity of hydrogen should be controlled at 25%–50%. This paper proposes mass fraction difference coefficient, as uniformity evaluation index. When hydrogen relative humidity is 50%, uniformity of reactants distribution is the best.