Analysing Gas-Liquid Flow in PEM Electrolyser Micro-Channels Using a Micro-Porous Ceramic as Gas Permeable Wall

Gas-liquid flow in micro-channels of a polymer electrolyte membrane water electrolysis cell (PEMEC) is studied ex-situ experimentally. In this study, the anode transport layer and micro-channels of an interdigitated flow field are visualised. A micro-porous ceramic is used for uniformly distributing gas. Different gas-liquid flow regimes like bubbly flow, Taylor flow and annular flow are noticed. These gas-liquid flow regimes are found to be dependent on current density and water stoichiometry. Furthermore, wall dry out in Taylor and annular flow regimes is noticed. This phenomenon is due to the channel cross-section aspect ratio and gas-liquid wall contact angle. This study gives knowledge about the flow plate design for high mass transport and heat transfer rates to and from the transport layer.