.... This can be seen from the longer error bars in Fig. 8( a ) . This could be due to a combination of high temperature, low humidity, low anode stoichiometry, and high pressure. The issue is removed for the other two curves, where pressure and temperature were lowered and the anode stoichiometry...

... with the steady state isotropic transient kinetic analysis (SSITKA) method. The effect of the humidity level on desorption kinetics was quantified. The carbon monoxide (CO) desorption kinetic constant was calculated regardless of the gas flow rate. The kinetic constant dropped up to 58% with the increasing...

... corresponding to the inception of two-phase flow, called the threshold current density, is found to be a function of the channel length and height, GDL thickness, velocity, and relative humidity of the air at the inlet and cell temperature. Thus, for given design and operating conditions, the analytical model...

... considered. The evolutions of their coordinates in the Nyquist plot can be monitored versus aging time and for different gas utilization rates. 23 05 2008 11 06 2009 20 01 2010 20 01 2010 durability electrochemical impedance spectroscopy humidity mechanical testing membranes...

... to be the reason for a large voltage drop. SOFC cathode humidity degradation Solid oxide fuel cells (SOFCs) are promising power generation systems with various advantages, such as high energy efficiency and multifuel capability ( 1 2 3 4 ). In their practical operation, however, various kinds...

... distribution of the entire module as well as of the oxygen concentration and relative humidity at a specific cell. Airflow near the cathode in a single cell was also visualized. It was concluded that the power breakdown was probably caused by flooding in the anode of one of the most downstream cells...

... as a function of temperature and humidity is proposed. To this end, the G’Sell–Jonas (1979, “Determination of the Plastic Behavior of Solid Polymers at Constant True Strain Rate,” J. Mater. Sci., 14, pp. 583–591) constitutive model for semicrystalline polymers is extended by incorporating, in addition...

... of 25 cm 2 with Nafion ® 117 membrane. Triple serpentine designs for the flow fields with two different flow depths were used in this research. The experimental results indicated that the relative humidity and temperature play an important role with respect to fuel cell performance. The fuel cell needs...

...Fabio Rinaldi; Renzo Marchesi The aim of this work is the performance study of a polimeric electrolyte membrane stack. Extreme conditions of temperature and relative humidity, such as those that may be found in practical situations (i.e., automotive), have been considered. The research has been...

... geometry test cell with serpentine channels and counter flow. Subsequently, the model is applied to explore cell temperature effects in the cell environment with different relative humidity of inlet. The numerical model is validated and agreed well with the experimental data. The nonuniformity of thermal...

... is useful in investigating the current density distribution in a single cell as well as a stack, which carries the information about the local reactant activity over the electrode area. It was found that the current density close to the gas inlets is strongly influenced by the reactants' relative humidity...

... and membrane Ohmic overpotential. Overall, good agreements between the simulated results and the experimental data were obtained. However, at large current densities, with high relative humidity reactant inputs, the simulation under-predicted the fuel cell performance due to the single-phase assumption...

... heat generation. In the anode channel, on the other hand, the phase change is less likely to occur even if the inlet hydrogen is humidified with a high relative humidity value. The model is partially validated using the experimental data from open literature. A series of analyses are carried out...

...-osmotic drag and diffusion depends not only on operating conditions, such as current density and relative humidity at the membrane boundaries, but also on design parameters, such as membrane thickness and membrane material. Computed water fluxes for different humidity boundary conditions indicate...