PEM 电解池氧气分布及压缩条件下性能研究

Proton exchange membrane electrolysis cells (PEMEC) are widely considered ideal devices for coupling renewable energy sources to produce green hydrogen. However, the local oxygen distribution characteristics within the electrolysis cell and the effect of assembly pressure on cell performance are not yet well understood, posing significant challenges for optimizing the cell structure and enhancing its performance. In this study, the ANSYS Fluent with the user-defined function code is first employed to simulate the three-dimensional multiphase and multi-physical fields of the electrolysis cell. The influence of porosity and contact angle on the oxygen distribution within the porous electrode is investigated. Then the accumulation characteristics of oxygen in the flow channel are determined by the volume of fluid (VOF) method and image recognition, and coupling iteration with the full cell model. Furthermore, a contact resistance model is proposed to analyze the performance of the electrolysis cell under different compression conditions. Results indicate that increasing porosity and reducing contact angle can enhance the mass transfer under the land, and oxygen bubbles tend to generate near the land, subsequently accumulating and growing towards the center of the channel, forming plug flow. When the current density is 0.8 A/cm², neglecting the contact resistance would underestimate the voltage by 0.17 V.