(Invited) Numerical Simulation Approaches for Understanding Transports Behavior inside Polymer Electrolyte Membrane Fuel Cells

Abstract

Augmentation of polymer electrolyte membrane (PEM) fuel cell (FC) performance at high current densities, particularly under automotive application, is important to improve the overall power density and to reduce the cost of PEMFC systems. Primarily, the fundamental non-linearity of the equations governing PEMFC performance on a three-dimensional model necessitates iterative solutions. As of now, mass transport over-potential is a major barrier to achieving high performance at a high current density. Experimental investigations of oxygen transport in particular are limited by an inability to resolve the water saturation-dependent properties. The alternative approach to understand and overcome transport resistances, predominantly inside the gas diffusion layer, is to use advanced numerical modeling.Numerical simulation techniques using in PEMFC will be presented including conventional computational fluid dynamics and the meshless Lattice Boltzmann method (LBM) which is an alternative advanced modeling technique [1-14]. This approach can be applied to existing models to visualize the transports inside the structure of microscale geometries, such as: a gas diffusion layer (GDL), micro porous layer (MPL), and catalyst layer (CL). The study where the goal was to use these numerical approaches and directly predict the transports behavior across the length scale (macro-, meso-, micro-, and nano- scales) as shown in Figure 1. The understanding of local kinetic activity inside nanoscale CL implemented into the model will also be discussed. The achievement of this work can enhance the potential capability of a model-based investigation of transport physics inside PEMFC to find solution of designs and operational conditions especially for transport applications.