Effects of GDL porosity and fiber diameter on the performance of a PEM fuel cell by lattice Boltzmann method

High power density, low operation temperature, high efficiency and low emissions have advantages of polymer electrolyte fuel cells (PEFCs) among all electrochemical power sources. In conventional numerical simulations of PEFCs the porous electrodes are considered as isotropic and homogeneous media, while in reality they have a complicated anisotropic and non-homogenous microstructure. Therefore, pore-scale modeling techniques such as lattice Boltzmann method (LBM), which are capable of considering anisotropy and non-homogeneity effects, have recently gained a great attention for PEFC simulations. However, PEFCs simulation by LBM has faced with some challenges in modeling electrochemical reactions in the catalyst layer. In the present study, a three-dimensional pore-scale model based on LBM is proposed for the cathode electrode of a PEFC in which the electrochemical reaction is taken into account for the first time also in this work investigated influence porosity and fiber diameter on the performance of a polymer electrolyte fuel cell (PEFC). The model enables us to simulate multi-species transport in a heterogeneous and anisotropic porous gas diffusion layer (GDL) through an active approach. After model validation, several simulations are performed to investigate the effects of GDL microstructure on the species and current density distributions. The results demonstrate that GDL microstructure has a considerable influence over the mentioned parameters

کلیدواژه ها:

polymer electrolyte fuel cell ، pore-scale model ، cathode electrode ، microstructure ، electrochemical reaction ، lattice Boltzmann method