Effects of the Structure, Wettability, and Rib-Channel Width Ratio on Liquid Water Transport in Gas Diffusion Layer Using the Lattice Boltzmann Method

• Published in: Energy & fuels 2021-10, Vol.35 (20), p.16799-16813
• Main Authors: Liao, Jiadong, Yang, Guogang, Shen, Qiuwan, Li, Shian, Jiang, Ziheng, Wang, Hao, Sheng, Zhonghua, Zhang, Guoling, Zhang, Hongpeng
• Format: Article
• Language: English
• Subjects: Fuel Cells
• ISSN: 0887-0624; 1520-5029
• DOI: 10.1021/acs.energyfuels.1c02023

The gas diffusion layer (GDL) plays a key role in water management. The effects of the structure, wettability, and rib-channel width ratio on liquid water transport in GDL are studied using a multiphase lattice Boltzmann method (LBM) model. It is found that the liquid water in GDL shows capillary fingering behavior. With the increase of carbon fiber diameter or porosity, the water saturation in GDL increases, and the time for liquid water to break through GDL decreases. The porosity has a significant effect on the water saturation in GDL. The water saturation of GDL with a contact angle of 140° is less than that of GDL with a contact angle of 80°. The water saturation in GDL decreases as the rib-channel width ratio increases, while the rib-channel width ratio has little effect on the water saturation in the region of GDL away from the rib. Compared to the rib with a contact angle of 140°, the rib with a contact angle of 60° slightly reduced the water saturation in GDL, and the wettability of the rib has only a small effect on the water saturation in the region of GDL near the rib.