Numerical Study of the Effect of the Inlet Pressure and the Height of Gas Channel on the Distribution and Consumption of Reagents in a Fuel Cell (PEMFC)

Proton exchange membrane fuel cell (PEMFC) engines can potentially replace the internal combustion engine for transportation because they are clean, quiet, energy efficient, modular, and capable of quick start-up. Since a PEMFC simultaneously involves electrochemical reactions, current distribution, hydrodynamics, multicomponents transport, and heat transfer, a comprehensive mathematical model is needed to gain a fundamental understanding of the interacting electrochemical and transport phenomena and to provide a computeraided tool for design and optimization of future fuel cell engines. This paper analyses the effects of inlet pressure and channel height on the distribution and consumption of reagents. The gas flow is assumed laminar, unsteady, isothermal and incompressible, flow fields of the anode and cathode sides are modeled as straight channels. The equations of conservation of mass, momentum and species are developed. A program based on the finite volume method was performed to simulate the system of equations governing the phenomenon. The simulation results show that increasing the inlet pressure will improve consumption of reagents and more homogeneous distribution. The effect of channel height on the consumption of reagents is such that, if the height is smaller it is noticed that there is an increased consumption of species and consequently an increase in water production. Channels with smaller heights have shown a higher concentration of oxygen and hydrogen. The effect of height is more important for a higher pressure inlet.