Investigation of Water Droplet Interaction with the Sidewalls of the Gas Channel in a PEM Fuel Cell in the Presence of Gas Flow

Water appears as a byproduct during normal operation of Proton Exchange Membrane Fuel Cell (PEMFC), and stagnates on the gas diffusion layer (GDL) affecting its performance under certain operating conditions. The primary goal of this study was to develop an ex-situ experimental setup to analyze the sidewall interactions and droplet dynamics under controlled gas flow rates. The channel open angle was varied from 30° and 90° and the superficial air flow velocities between 0.2-2 m/s. The growth of the droplet and its interaction with the side wall were captured using a high-speed camera with a microscopic lens. The experimentation revealed that the droplet-side wall interaction was dependent on the gas channel angles and also on the gas flow rate. The study provides an insight into the droplet removal process in a PEMFC and provides guidance in the gas channel design.