Modeling of Flow and Transport Processes Occurred in a Typical Polymer Electrolyte Membrane Fuel Cell (PEMFC)

Abstract

In the present work, a three dimensional model examining the fluid flow along with the fundamental transport phenomena occurring in a typical polymer electrolyte fuel cell (PEMFC), i.e. heat transfer, mass transport and charge transfer, has been developed. The flow field was simulated according to the well known Navier-Stokes equations, while the heat transfer was described by the typical conduction/convection equation and the mass transport by the convection/diffusion one. Furthermore, reaction kinetics were studied by the Butler-Volmer equation for the heterogeneous reactions occurring at the porous electrodes. The developed model was numerically solved by using the commercially available CFD package CFD-RC©, which is based on the multi-step finite volume method. The fuel cell performance in terms of velocity, temperature, mass fractions of active compounds and electric field has been investigated as well.

Theoretical Investigation of the Relation between the Output of a Methane Internal Reforming SOFC and the Composition of the Feedstream

“…In general, most of the research correlates the efficiency of the fuel cell with the macroscopic operational parameters, based on the first and second laws of thermodynamics [5]. The main drawback of such approaches is that the transport processes occurred in micro-and meso-scaling level are not usually taken into consideration, although they have been proved to be very important for the power production in fuel cells of any type [6]. As a first step to this direction, the main objective of this work is to identify the dependence of the current density on the CH 4 concentration in the feedstream, by taking into account the transport processes occurred.…”