Numerical analysis of PEM fuel cell with a serpentine flow channel

Nowadays an increasing demand for energy and limited energy resources as well as health and environmental concerns have initiated studies for new generation of energy technologies which are more efficient, more clean and compatible with renewable energy sources. Because of fuel cells have high efficiency, high current density and low emissions besides quiet operation, they are thought to be the most promising energy conversion technologies.In this study, PEM fuel cell with serpantine channel was analyzed as a single-phase, non-isothermal, steady state and in three dimensions. PEM fuel cell is composed of nine layers including the gas channel, the current collector plate, the gas diffusion layer, the catalyst layer for the sides of anode and cathode and membrane layer. ANSYS FLUENT 12.1 package program was used for simulations. Simulations were carried out in two stages. First, simulations were made for different gas channel widths and thicknesses of the membrane. After determining the appropriate gas channel width and the thickness of the membrane, the effects of operating parameters such as anode inlet humidity, inlet temperature of reactant gas, operating pressure and the gas flow directions on the performance of fuel cell were investigated. The results obtained from this parametric studies are shown in terms of polarization curves and analysis results of the temperature, pressure, current density, velocity and concentration distributions (H2, O2, and H2O mass fractions) are presented in graphs. The results of analysis were compared to similar studies in the literature. Simulations shown that the increase in the gas channel width, anode inlet humidity, reactant gas inlet temperature and the operating pressure increases the cell performance. Flow of anode gases and cathode gases in opposite direction also has a positive impact on the cell performance. However, increasing membrane thickness causes a decrease in the cell performance.Key Words : PEM fuel cell, computational fluid dynamics, serpentine channel