Three-Dimensional Lattice Boltzmann Simulation of Liquid Water Transport in Porous Layer of PEMFC

Entropy

Bo Han²  Meng Ni³  Hua Meng²  Ignazio Licata¹  Sauro Succi¹ 

[1] School of Aeronautics and Astronautics, Zhejiang University, Hangzhou 310027, ChinaSchool of Aeronautics and Astronautics, Zhejiang University, Hangzhou 310027, China;Department of Building and Real Estate, Hong Kong Polytechnic University, Hung Hom 999077, Hong Kong, China;

关键词: lattice Boltzmann model;    two-phase transport;    microstructure reconstruction;    porosity;    liquid saturation;   

DOI  :  10.3390/e18010017

来源: mdpi

【 摘 要 】

A three-dimensional two-phase lattice Boltzmann model (LBM) is implemented and validated for qualitative study of the fundamental phenomena of liquid water transport in the porous layer of a proton exchange membrane fuel cell (PEMFC). In the present study, the three-dimensional microstructures of a porous layer are numerically reconstructed by a random generation method. The LBM simulations focus on the effects of the porous layer porosity and boundary liquid saturation on liquid water transport in porous materials. Numerical results confirm that liquid water transport is strongly affected by the microstructures in a porous layer, and the transport process prefers the large pores as its main pathway. The preferential transport phenomenon is more profound with a decreased porous layer porosity and/or boundary liquid saturation. In the transport process, the breakup of a liquid water stream can occur under certain conditions, leading to the formation of liquid droplets inside the porous layer. This phenomenon is related to the connecting bridge or neck resistance dictated by the surface tension, and happens more frequently with a smaller porous layer porosity. Results indicate that an optimized design of porous layer porosity and the combination of various pore sizes may improve both the liquid water removal and gaseous reactant transport in the porous layer of a PEMFC.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.